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XNA 2D Transformation

I have actually the following map (isometric projection), and I can move/zoom/rotate without problem with matrix transformations (SpriteBatch): picture.
And I wanted to know if it was possible (if so, how), to get the following result, without referring to 3D: picture.
All suggestions are welcome. Thank you in advance. :)

Its going to be a huge pain in the ass, especially but I think it is at least possible if you don't change the viewing angle.
Some ideas:
Make each tile its own little image unit.
The more far back the tile is from the camera, lower its layer priority when you draw it so that it gets blocked by tiles in front of it. Also you will have to figure out an algorithm that correctly sizes the tiles based on their distance. This algorithm will have to be more and more precise the closer you want to get the tiles, but there should be some mathematical/geometric formula that can do it automatically.
You quite literally CANNOT rotate the camera at all, unless you want to have separate sprites for every single angle for every single tile.

Texture/model flickering in distance (3D)

Ok, in my XNA project i've added simple shader + model loading code, anything works. I created a very simple low-detailed model in 3Ds Max. Exported and imported to XNA with FBX format.
The problem is:
if i move my simple camera to some distance from this model, one of its components starts to flicker. I tried another model and there is the same situation, some of components start to flicker and only if i get to some distance from model.
This flickering (or blinking or ..) appears only with textured objects (probably), and looks like:
in each frame random parts/pixels of model (or not so random) replaced with object which is behind a model or its component... :(
UPDATE: Now i know - problem is in my model (i checked some other models). I dont understand why but Plane object gives that flickering. Maybe the problem is not in Plane object.

This is only an educated guess but: Your far-plane is too far away, or your near-plane is too close, or both.
A perspective camera gives you a viewable area that looks like this:
Your Z-buffer (depth buffer) covers the range between the near and the far planes. A typical Z-buffer might have 24-bits of precision, giving you 224 possible values. The further apart your near and far planes are, the greater the world-space distance each possible value must covers. In other words: your Z buffer is less accurate.
What you are seeing is known as "Z-fighting". This is where the Z-buffer is not accurate enough to differentiate between the depths of two given pixels. So you end up with pixels that should have been rejected as being "behind" what was already rendered, drawn instead.
(Alternately your model has some coplanar or nearly coplanar triangles - that is triangles who's surfaces are too close together. Same issue: Not enough precision in the Z-buffer to differentiate between the two surfaces.)
You may also wish to enable backface-culling (RasterizerState.CullCounterClockwise), if it is not already enabled. This culls triangles facing away from the camera, removing one possible source of Z-fighting.

I have seen this happen before on models where there are two or more surfaces overlapping in the same plane, one surface is inside the other but in the same plane - so the system can not tell which surface is in front of the other and usually ends up with a mash-up of both surfaces.
It looks like you have a smaller rectangular surface intersecting with a larger rectangular surface that makes up the lower base shape of your model. Probably from another object inside the box? Or from a object subtraction error that left two rectangles inside each other on that surface maybe?
Either way modify the model so there are no longer two surfaces with in each other.

Draw points along the surface of a cube

So for an assignment I have to morph a cube into a sphere. All that's required is to have a bunch of points along the surface of a cube (don't need to be connected or actually be on a cube, but has to form a cube, though connections would make it easier to look at) and have them smoothly translate into a sphere shape.
The main problem is I never learned how to make points in XNA 4.0 and from what I've seen it's very different to what we did in OpenGL (we learned the old one in a previous class).
Would anyone be able to help me figure out making the cube shape I need? Each side would have 10x10 points with the points on the edge shared by the surfaces of that edge. The structure would need to be easy to copy or modify since I would need to have the start state, end state, and the intermediate state to translate the points between the two states.
If I left out anything that could be important let me know.

First of all, you should familiarise yourself with the Primitives3D sample. It illustrates all of the rendering APIs that you need.
Here is how I would approach this problem (you can look up these classes and methods on MSDN and it will hopefully help you flesh out the details):
Create an array of Vector3[] that represents an appropriately tessellated unit cube around (0,0)
Create a second array of Vector3[] and and use Vector3.Normalize to copy in the vertices from your first array. This will create a unit sphere with vertices that match up with the original cube.
Create an array of VertexPositionColor[]. Fill in the colour data however you like.
Use Vector3.Lerp to loop through the first two arrays, interpolating each element to set positions in the third array. This gives you a parameter you can animate - you will have to do this each frame (in Update is probably best).
Create an array of indices (short[]) that describes a triangle list of the tessellated cube (and, in turn, the sphere and animation between the two).
Set up a BasicEffect for rendering. This involves setting its World, View and Projection matrices and maybe turning on VertexColorEnabled. If you want lighting, see the sample for details (you'll need to use a vertex type with normals, and animate those normals correctly).
The way to render with an effect is: foreach(EffectPass effectPass in effect.CurrentTechnique.Passes) { effectPass.Apply(); /* your stuff here */ }
You could create a DynamicVertexBuffer and IndexBuffer and draw with those. But for something simple like this, DrawUserIndexedPrimitives is much easier (here is a recent answer with some details, and here's another one with a complete example of BasicEffect).
Note that you should only create these objects at startup (LoadContent is a good place). During rendering you're simply using them.
If you have trouble with your 3D rendering, and you're drawing text or sprites, see this article for how to fix it.

How to simulate a card been played in a card game?

I am developing a card game using WPF and since i do not have any knowledge about animations i would like to know if someone could help me in how to write an animation to simulate a Card ( Image ) been played over a table.
At the bottom and top of my game table i have my cards on vertical position.
At the right and left my cards are on horizontal position.
What i really want is give an impression that a human is selecting and throwing the card.

Since your question is pretty open-ended, I'll give you an open-ended start...
Look into Storyboards, and how to use the same to modify the RenderTransform of your Card UserControl.
Your first step should really just be animating your card's position from its initial spot to the center of the table. As an additional hint (which will come in handy after you've learned about Storyboards), your DoubleAnimation.From property does not need to be specified. You just need to specify the DoubleAnimation.To property.

I see questions like this all the time on SO, and it really does give the impression of "I haven't tried, and I have not read anything". You already have your cards on the table (so to speak), and the question is, make it look like a human did it.
There are a variety of ways, some cheap and simple, some more complex and involved. You won't know the answer until you try.
For example, perhaps you want a card to go from one position to another (optionally flipping). You have varying degrees of difficulty here:
Move the card to the position, as is. Cheap and easy. You could even use the distance between the source and the target to determine the speed to have some kind of residual momentum.
Cards are at different angles. How do we rotate? XNA makes this pretty simple, have you looked up on XNA and general rendering? Or do you want to this purely using WPF?
Does the move involve showing the card face-up, or not? Will there be an animation involved? Are you happy with just the face changing or do you want to see an actual "flip"? If it's the latter than some kind of a plane in XNA using 3D might be better, at least then you can have two faces with two different textures.
What I am saying is, and why this is an answer as opposed to a comment, is that you have given no indication of anything that might be considered trying to solve the problem. You seem like you've got halfway there, you've already got cards rendered on the screen. But to ask "Make it look like a human put a card in"...? Well, sorry... it's not that simple. You can make this task as easy or had as you wish.

Collision detection 2D between rectangles

I am writting a collision detection engine for my game and I have some problems.
Indeed, since I have several fixed rectangle and one moving (the player), I need to know which side of the fixed one was collided at first by the player, to replace him correctly.
The fixed rectangle are NOT in a grid so they can be placed anywhere on the map and they can have diffents size. They are not rotated.
The player class stores it's direction vector.
Any idea?
KiTe

In a nutshell:
You'll compare the Y and X components of the bounding rectangles to eachother to check for a collision. If the top(Y) of the player is less than the bottom of an enemy then you don't need to check anymore because it's not possible that they're colliding. If the right(X) side of the player is less than the left side of the enemy then they can't be colliding. It would help to define top, right, bottom, left of each object you intend to check inside the class. This will allow you to know which side is hit also. This should be enough to get you thinking and experimenting.
Have fun!

The name is "Axis-Aligned Bounding Box" collision detection.
Now you know the name, you can Google for the rest.

thanks to both of you for your help.
I've heard about AABB, but at first sight it didnt seem to fit to my needs (since I didn't understand it well).
But after writing down everything on papper, the solution I found appeared to be exactly the same as AABB !