I have found that when I zoom in to the max. it looks a bit pixelated; so I most often use the next level zoom.
The CD version makes planning and playing much easier because you can see so much more of the battlefield at a glance. The map doesn't feel restricted, where I have to pan around or zoom right out in order to view the situation.
My desktop is at 1680x1050, I play winSPWW2 at 1280x1024 in a window so that it doesn't get stretched horizontally. I also am one click out from max zoom it and the game is pretty easy to see and play. I also like playing in a window since I can keep the game manual up.