Can someone please help me?

I don't know where to place this message or how to explain my situation.

I have a cyberstalker and he is a hacker. In the past 2 years I have had to purchase three computers because of worms, trojan horses, etc. being placed on my computer and one computer was less then 6 months old when the hard drive messed up.

I'm a College Student and I do some of my homework over the internet and i upload it to our College's Website. This guy hacks into computer systems and has showed up at my campus before. He frequents the same web boards and even if i change my screen name he finds a way to get into my computer again.

I have Norton as a firewall and I think that he can get into a back door anyways because he has before.

My question is: What is PAL Evidence Elimanator and would it remove information about my internet cafe locations that i go to? Is there a firewall that someone can use that would prevent someone from getting into a "back door"?
What would you reccomend that I use that would clear all of the internet cafe, homework, email, etc. evidence off of my computer?

I am in desperate need of help and any suggestions would be greatly appreciated.

 

firstly you should insure that all patches are up to date on your system (OS,AntiVirus,Firewall) you really need to read these helpfull notes
here
http://forums.majorgeeks.com/showthread.php?t=25834
and here
http://forums.majorgeeks.com/showthread.php?t=44525

hope this helps any questions post back.