Windows XP Keeps resetting back to stock... sorta.

Well, this is a first for me, never seen this problem pop up in Windows before but here goes:


I just built my new PC, installed windows, patched to SP3, updated all my drivers, yadda, yadda.

I've been working on this PC for over a month now, and all of the sudden, it's starting to "lag". I've had to Force Reboot twice today because it just stops responding. Sometimes it will work all day, no problems, sometimes all hades breaks loose.

Well the actual problem I'm here to ask about is this. Somehow, Windows has up and deleted all of my recently downloaded files. It's acting like it's a fresh install. Wanting to show me how everything works, IE 7 resets back to the default MSN page. It's NOT deleting all of my programs though.. just all the things I've done with them. Save Games for my Installed Games, etc.

I'm not 100% sure what's going on here. It's not asking me to restore to a previous date or anything. it's just loading Windows normally, and when I get to the desktop, everything is gone.