This problem simply has me stumped. I remember on my old computer, Win95, every once in a while my desktop would mysteriously be reset upon booting up.
But this isn't exactly the same thing.
I have WinXP Professional. Basically, one of my family members will be on the computer, and then out of nothing, the "Please Wait" flat dialog box will pop up on the screen. After a few seconds, the theme will reset to Windows Classic (Its set at Windows XP currently!) So basically, the computer is behaving just like you selected a new theme in Display Properties, and hit OK. Except we aren't even DOING anything display related. It does it maybe 15-30 minutes after a user account is open (or sooner, or later. Once its set at Windows Classic, I don't think it does it again)
The funny thing is, it has NEVER happened on MY user account! Only on my parents account, and my sisters' account. My Windows XP theme has never reset while I was using the computer, only on the other user accounts. I've done virus checks, and ad-aware. Is it possible it's some kind of setting thats not in my user account? This problem is really getting on my nerves.