Sound like you have a project ahead of you. I have many questions for you, but we can work on this a step at a time. When you say you tried re-installing windows....what steps did you take to attempt the re-install? Do you have any funtionality such as accessing safe-mode? Are you able to get into BIOS to change boot sequences? Do you have a back up stored anywhere? Are you prepared to formatt your harddrive if necessary? Do you know how to do a simple repair on your XP OS? This is a start, but you could have many different things happening, and I need to know what you can and cannot do at the moment with your PC! Good luck!