I agree about the antivirus. You can check the test results of the various makers, but I don't think they matter that much. Keep your av updated and maybe even run an online scan from one of the other makes periodically. As for firewalls, agnitum, kerio and sygate are good. Firewalls, too, depend on stayin current. Check occasionally for a newer version and stay on top of it. There isn't much else to do other than leaving the computer turned off.