You can buy the full version of AVG plus firewall for $24 for 2 years. I love it and it doesn't take over my computer. I hate that! I also run Ad-aware and sometimes Spybot just for GP.

The important thing is to USE the software you have. Set it up on a schedule. I run a full scan everyday...without fail.
And I don't use Limewire!!!!!!! Cost me $150 to get my puter fixed after using that crap. That was the most expensive music I ever downloaded....LOL I just buy it now.