Let's start with the basics. Follow this process here to create a new user account:
Gł - Windows > XP + General: Corrupt Profile:
Gł - Windows > XP + General: Corrupt ProfileGetting a new drive and installing an OS on it would help you get your files back but that may not be the problem at all. Try a new profile first and see if that does the trick for you and we can run from there. Make sure to follow the steps exactly. Just so you know you can open the control panel (hopefully) by using the "control" run prompt or you can get there directly by running "control userpasswords" if you would like.