a virtual desktop is exactly what is sounds.. a virtual desktop. If your running a game that runs in a window, its going to run in its normal window on the virtual desktop... its a desktop, so if the game is trying to run fullscreen, it will take up the whole virtual desktop because it sees that desktop as its 'monitor' if you will. There is little point running a windowed application in a virtual desktop if it will run without one. Wine will not scale graphics to change their sizes... if the graphics is trying to draw 20 pixels by 20 pixels, its going to do the same in Wine as on Windows and draw it 20 pixels by 20 pixels.
