how can i fix my computer?

Personally I find the thing called Google is really useful fo rthis kind of question.

I typed "windows xp instalation instructions" in the Google search box and some results came back. Here are the very first two, which should give you everything you need:

http://www.winsupersite.com/showcase/windowsxp_sg_clean.asp

http://support.microsoft.com/kb/316941

Finally, as soon as you've installed Windows, download and install some decent antivirus software - try here: http://free.avg.com/download?prd=afe

Install it and keep it updated.

Also, now - BEFORE you run into any problems with nasties, go visit www.whatthetech.com and browse the help forum, learn about hijackthis and what it is useful for.

You wouldn't consider driving a car without learning how to drive, so try to learn about your PC before you start to use it.

Jon
September 2009