Well I have always used the latest nortons internet security system ( 2004 right now )
And i hardly get spyware or viruse;s on this pc and its used 24/7 nearly by myself and other people, i regular scan for problems with nortons anti virus scanner, and with system mechanic and spybot 1.3 plus the new ad-aware SE, and nothing gets on this pc without me knowing about it
Ahhh and spyblaster runs in background