I've used Norton for most of the time i've been on the net, although i don't have anything installed at the moment hehe. My dad hates it though, he uses something called Avira AntiVir i think... and being a network technician all his life i should probably listen to him and install that haha

http://www.avira.com/en/pages/index.php

Is the home page if you need it. Its pretty cheap as far as antivirus program go, so definatly worth a look. Also i'd suggest installed programs like Adaware or Spybot to go along with it, they tend to remove a load of crap from your computer aswell XD