If I upgrade...

I have an old copy of WinXP sitting in my CD rack... I installed it on an old computer, which is now sitting in a thrift shop (hd not in it, of course). My question is, can I upgrade from windows 2000 on a completely new computer to my winxp copy? And if I do, will I have to format, or can I just keep all my programs?

I'd prefer not to format because I have so many settings stuck on my system, that reformatting would take at least 3 days, time I don't have.

For Win2k you can only upgrade to XP pro. You will have to call MS and let them know why XP is on a new machine. You will not have to format but it is best to do so, I have found that upgrading can be more of a pain that just reinstalling.

I have upgraded a couple of machines to XP Home from 2000 with no problem. I always do a complete reformat and reinstall.