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Programming with .net

I've just recently learned C# and am interested in .net but I don't know where to begin.
I know .net is just a bunch of libraries and can be used for web programming?
I'm not quite sure what areas in .net that I need to learn?
I don't know what I am trying to accomplish with .net? But I want to learn .net.
What other things can be achieved with .net?
Thanks.
Added -
The 2D class that I finished was a C#/Winform/XNA class working with 2d objects. Though there was never once a reference about .net in class. I just learned C# which is comparable to C++ and Java and Winform = just using the tool box and hooking up controls to back end code. XNA portion was being able to use the hardware to draw primitives and manipulate data going through the model->view->project pipeline.
What part of this class was .net? None right?

You can do nearly anything with .net (the same is true for most other platforms).
You can use ASP.NET for web programming, Windows Forms or Windows Presentation Foundation for GUI development.
There are also lots of functionality for networking, database development and XML or Image processing.
But the question is, what do you want to achieve?

I know .net is just a bunch of libraries and can be used for web programming?
.NET is much more than this. It is not restricted to web programming. There are possibilities for doing Windows Applications (WPF), Web Applications (ASP.NET), Network Communication (WCF), Database Access (ADO.NET), ..., you name it. So just pick a language you would like to learn like C# and go ahead and visit MSDN.

.Net is a managed runtime with libraries. It is not exclusive to building "web" applciation or pages.
The .Net Framework is 'the libraries'.
The CLR is the runtime (where the specification thereof, is deposited into a standarization organization)
C#/VB.Net/F# are flavors of different syntaxus (how do you spell this in plural?) used to instruct the runtime, using the libraries, to perform actions in an order you define (AKA programming)
Wanting to learn .Net is akin to learning another language/gammar. If you have no previous knowledge of "language/gammar" itself, you are using this specific language/runtime to learn 'language' in general.
Hope this helps,

Sorry, but if you've just used the toolbox to hook some stuff together you haven't learned C# or programming. You've learned how to hook some stuff together, but you're obviously interested in learning how it works. Seems like you're going to have to learn a lot of stuff from scratch. There's a lot to learn...
I think your best bet to learn .Net and C# (you can't really learn one without the other) apart from following a course specific for that goal is to find yourself a good book that explains the whole picture and run through the examples in the book.
Looking on internet, asking questions, and collecting bits of examples, etc. will give you little pieces of understanding, but I doubt you'll be able to get a comprehensive understanding of programming, .Net and C# that way, simply because you won't find a big picture explanation. I find a good book gives me a deeper understanding even though I've already worked with .Net/C# since it first came out, simply because there is much more explanation of how things work and why.
Personally I really like the Pro series from Apress: have a look at Pro C# 2010 and the .Net 4 Platform
It might be perfect or not depending on your understanding of software development. Otherwise just search for C# and see if other interesting books pop up.

What are the first steps in C#/.NET development?

Okay, I'm biting the bullet and deciding to get into the whole Microsoft/C#/.NET culture and I'm going to do this by putting together a simple (hah!) application.
It will basically be an application in which I want to store images and associate with them other optional things.
It must be able to import images from the filesystem (and hopefully camera/scanner) then allow the user to add text, audio and other information.
I plan to store the images and auxillary information into a database. What the application will do with said data isn't important (yet).
Keep in mind I know absolutely nothing about C# or .NET although, as an old codger, I know a great deal about many other things and will regale/bore you with stories and anecdotes until you quietly slip away :-)
What are the first steps to take in developing such an application? I've already set out UI layouts and likely process flows although it may be that the development environment dictates changes.
Development environment is currently XP SP3 + VS2008 (though I can upgrade if absolutely necessary).
What should I be looking at as the first step? Are there any gotchas I should be looking out for?

Have you decided for win forms or WPF? I've been doing win forms for the past 4 years and WPF was a great discovery for me, with the flexibility it affords. It might be fitted for your application and the different types of content you'll want to add and give you a flexibility that win forms can't give.
As for actually developing, I think loading images from the disk would be the first step, showing them in the UI and getting user input for them - you would get to work with the different objects and see how the framework handles things.
A tutorial about the field validation I mentioned in my comment is here - haven't done it, but something similar. You can also see the xaml code paired with the C# code there.
After looking for the differences between win forms and WPF I found that there are a few win forms controls that are missing from WPF. More on that on MSDN (compariosn chart) and a post from March with a more detailed chart.
It's also worth mentioning that you can include win forms controls in WPF applications and vice versa, but there are some limitations.

Just a couple of pointers, it would be easy to overwhelm you as you are just starting with this tech stack. First step, use SQLServer 2008 Express, it has better ability to deal with image data (images can be saved directly to the filesystem, but they are still in a table).
Apart from that, you can design your screen with the GUI, and then hook the bits up one by one to your retreived data. Create a new Windows Forms app, or a WPF one, and start from there (i'm assuming that you know about the toolbox window and just dragging components on to the designer and setting their properties in the Properties window).

If you're looking win forms you're going to have drag-and-drop UI pretty easily.
If you want to use a database than you're probably going to find MS-SQL the easiest to cooperate with. Look up LINQ-2-SQL, it lets you access your database through an object layer by simply dragging your tables onto a pane.
Fun things to use: extension methods, partial classes, LINQ (query any collection with inline lambdas) and even class/method attributes.

My $0,02:
a) Get to know the platform a bit, types, collections, events/delegates(/lambdas), etc etc
b) Dive into WPF
c) Learn about database connectivity (LINQ2SQL or NHibernate (or ....)
d) Learn about the MVVM pattern to get to deliver solid wpf applications, doing so forces you to dive deeper into the workings of WPF (routed commands, tunneling/bubbleing etc)
e) Learn more about patterns to get a more solid grasp of OO (this: http://www.amazon.com/Design-Patterns-Explained-Perspective-Object-Oriented/dp/0321247140/ref=sr_1_1?ie=UTF8&s=books&qid=1276066663&sr=8-1 is an absolute pearl for that)
f) etc

If you aren't too desperate to get your hands dirty straight away I'd suggest this book: CLR via C#.
It is written for those with programming experience on platforms other than .Net and provides a clear and comprehensive explanation of C# and how it runs on the .NET CLR.
By reading this initially you might avoid writing some of the poorly constructed applications that many of us wrote before properly understanding the technology.

Buy a book on C# & .NET FW fundamentals!
Read! :-)

Read good books about .NET for example CLR via C#.
Read this:
Hidden Features of C#? https://stackoverflow.com/questions/380819/common-programming-mistakes-for-net-developers-to-avoid

Is it possible to write DirectShow filters in C# (not in c\c++)?

Is it possible to write DirectShow filters in C# (not in c\c++)?
I mean not only to create source filters but renderers or compressors etc?

Maxim Kartavenkov has written a lot of useful DirectShow articles on codeproject.com. Take a look at this article: Pure .NET DirectShow Filters in C#. It not only contains source filters, but also transform filters, renderers, encoders etc.
The code in his articles are not based on the directshow.net library, which is a good thing.

Yes it is. You can use the DirectShow.net Lib to help bridge the gap.
They even have a sample, if you look down the page you will see the GSSF sample description:
GSSF – The Generic Sample Source
Filter – A way to implement a source
filter in c#. If you have samples (for
example video frames from bitmap
files) that you want to use as a
source in a graph, this filter will
show you how.

You can, but it can be difficult unless you know DirectShow and .NET native interop pretty well. Even then it can be a little uphill.
Here is an example of it being done: http://www.sichbo.ca/Free_Code/100_C_Sharp_directshow_filters

I think implementing a complete DirectShow-Filter in C# is a bad idea. The C++ DirectShowBaseClasses are so helpful. To re-implement these will result in a complete mess.
If you want to implement a decoder/encoder or some audio/video-effect then you can create a DMO (maybe in C# but C++ would be better). If you need a Source-Filter, take the Ball-Sample and modify it. If you need other types of filters, then take a look at the samples (http://msdn.microsoft.com/en-us/library/windows/desktop/dd375468(v=vs.85).aspx) and modify one.

Basically you can export you .NET classes as COM. TO use DShow interfaces, simply link to CM objects from your .NET projects. Anyway, writing DShow filters in .NET without some support of libraries like BaseClasses for C++ could be challenging.

Learning C# after C++

In a progression of languages, I have been learning C and C++. Now I would like to learn C#. I know there are some drastic differences between them - such as the removal of pointers and garbage collection. However, I don't know many of the differences between the two.
What are the major differences that a C++ programmer would need to know when moving to C#? (For example, what can I use instead of STL, syntactic differences between them, or anything else that might be considered important.)

C# for C++ Developers is a great place to start. It is a table that lists the most important comparisons between the two languages.
Once you have explored some of these differences, you might choose a self-contained project you have written in the past in C++, and re-write it in C#. In your first pass, you will probably just end up translating directly across, using the same design and algorithms. As you become more comfortable with C#, you will recognize ways to take advantage of language features only available in C#, as well as the incredibly versatile .NET Framework.

I think it's important to note that pointers weren't really removed from C#, but that they still exist, they are everywhere, and they are called references.

Charles Petzold has a .NET Book Zero that is designed specifically for the C/C++ Windows programmer who wants to learn C# and .NET. It is a free PDF download from his site. All of the source code used in the book is available as a separate Zip-file download.

There was a similar question that has lots of pointers (pun inteded :-)) and resources about the differences between C++ and C# and what to pay attention when learning transitioning - Linux/C++ programmer to Windows/C# programmer.

Look at the Generic collections and LINQ (all the related technology to LINQ) for STL like functionality.
The number one thing to note is that ~/Destructor is c++ is nothing like the ~/finalizer in c# -- See IDisposable/using.

Comparing C# and Java

I learned Java in college, and then I was hired by a C# shop and have used that ever since. I spent my first week realizing that the two languages were almost identical, and the next two months figuring out the little differences. For the most part, was I noticing the things that Java had that C# doesn't, and thus was mostly frustrated. (example: enum types which are full-fledged classes, not just integers with a fresh coat of paint) I have since come to appreciate the C# world, but I can't say I knew Java well enough to really contrast the two so I'm curious to get a community cross-section.
What are the relative merits and weaknesses of C# and Java? This includes everything from language structure to available IDEs and server software.

Comparing and contrasting the languages between the two can be quite difficult, as in many ways it is the associated libraries that you use in association with the language that best showcases the various advantages of one of another.
So I'll try to list out as many things I can remember or that have already been posted and note who I think has the advantage:
GUI development (thick or thin). C# combined with .NET is currently the better choice.
Automated data source binding. C# has a strong lead with LINQ, also a wealth of 3rd part libraries also gives the edge
SQL connections. Java
Auto-boxing. Both languages provide it, but C# Properties provides a better design for it in regards to setters and getters
Annotation/Attributes. C# attributes are a stronger and clear implementation
Memory management - Java VM in all the testing I have done is far superior to CLR
Garbage collection - Java is another clear winner here. Unmanaged code with the C#/.NET framework makes this a nightmare, especially when working with GUI's.
Generics - I believe the two languages are basically tied here... I've seen good points showing either side being better. My gut feeling is that Java is better, but nothing logic to base it on. Also I've used C# generics ALLOT and Java generics only a few times...
Enumerations. Java all the way, C# implementation is borked as far as I'm concerned.
XML - Toss up here. The XML and serialization capabilities you get with .NET natively beats what you get with eclipse/Java out of the box. But there are lots of libraries for both products to help with XML... I've tried a few and was never really happy with any of them. I've stuck with native C# XML combined with some custom libraries I made on my own and I'm used to it, so hard to give this a far comparison at this point...
IDE - Eclipse is better than Visual Studio for non-GUI work. So Java wins for non-GUI and Visual Studio wins for GUI...
Those are all the items I can't think off for the moment... I'm sure you can literally pick hundreds of items to compare and contrasting the two. Hopefully this lists is a cross section of the more commonly used features...

One difference is that C# can work with Windows better. The downside of this is that it doesn't work well with anything but Windows (except maybe with Mono, which I haven't tried).

Another thing to keep in mind, you may also want to compare their respective VMs.
Comparing the CLR and Java VM will give you another way to differentiate between the two.
For example, if doing heavy multithreading, the Java VM has a stronger memory model than the CLR (.NET's equivalent).

C# has a better GUI with WPF, something that Java has traditionally been poor at.
C# has LINQ which is quite good.
Otherwise the 2 are practically the same - how do you think they created such a large class library so quickly when .NET first came out? Things have changed slightly since then, but fundamentally, C# could be called MS-Java.

Don't take this as anything more than an opinion, but personally I can't stand Java's GUI. It's just close enough to Windows but not quite, so it gets into an uncanny valley area where it's just really upsetting to me.
C# (and other .Net languages, I suppose) allow me to make programs that perfectly blend into Windows, and that makes me happy.
Of course, it's moot if we're not talking about developing a desktop application...

Java:
Enums in Java kick so much ass, its not even funny.
Java supports generic variance
C#:
C# is no longer limited to Windows (Mono).
The lack of the keyword internal in Java is rather disappointing.

You said:
enum types which are full-fledged classes, not just integers with a fresh coat of paint
Have you actually looked at the output? If you compile an application with enums in in then read the CIL you'll see that an enum is actually a sealed class deriving from System.Enum.
Tools such as Red-Gate (formerly Lutz Roeder's) Reflector will disassemble it as close to the orginal C# as possible so it may not be easily visible what is actually happening under the hood.

As Elizabeth Barrett Browning said: How do I love thee? Let me count the ways.
Please excuse the qualitative (vs. quantitative) aspect of this post.
Comparing these 2 languages (and their associated run-times) is very difficult. Comparisons can be at many levels and focus on many different aspects (such as GUI development mentioned in earlier posts). Preference between them is often personal and not just technical.
C# was originally based on Java (and the CLR on the JRE) but, IMHO, has, in general, gone beyond Java in its features, expressiveness and possibly utility. Being controlled by one company (vs. a committee), C# can move forward faster than Java can. The differences ebb and flow across releases with Java often playing catch up (such as the recent addition of lambdas to Java which C# has had for a long time). Neither language is a super-set of the other in all aspects as both have features (and foibles) the other lacks.
A detailed side-by-side comparison would likely take several 100s of pages. But my net is that for most modern business related programming tasks they are similar in power and utility. The most critical difference is probably in portability. Java runs on nearly all popular platforms, which C# runs mostly only on Windows-based platforms (ignoring Mono, which has not been widely successful). Java, because of its portability, arguably has a larger developer community and thus more third party library and framework support.
If you feel the need to select between them, your best criteria is your platform of interest. If all your work will run only on Windows systems, IMHO, C#/CLR, with its richer language and its ability to directly interact with Windows' native APIs, is a clear winner. If you need cross system portability then Java/JRE is a clear winner.
PS. If you need more portable jobs skills, then IMHO Java is also a winner.