Window Xp Pro followed by Windows Xp Home
64-Bit Edtion is a waste of time as there is not a lot of driver support out there.
Windows Media Centre Edition is Windows Xp Pro with a rather useless Media Interface. About the only thing that I like about MCE graphic card support on CRT TVs. For some reason, MCE provides me a much clearer image with the same video card and same driver than Windows Xp Pro. And this is on both 800x600 res and 1024x768 res
Windows Vista...... it's currently in Beta. However I would be waiting at least 6 months (or until the first service pack) before installing that.