For a good many years of Internet usage, I employed Norton, McAfee, and what not... but they all failed me. Every time after 4 or 6 months, my computer would be infected and I would have to Format the hard-drive to get rid of the pest problem! And then came the spywares, trojans and other e-vampires and hide in some corner of my machine and reproduce vigourously and wham! Another Formatting! My hard-drives would be grinded down layer by layer after each ordeal!
FINAL SOLUTION:
Now, for almost 4 years, I dont use any Antivirus or Anti-Spyware and still am free from any attacks. HOW?
All attacks come from the script level, binary script, ActiveX scripts. I simply turn them off in my browser. The machine has to ask me everytime it runs a script while surfing. When I'm in a safe site like this one which I know is free from malware, I press OK. When I'm in some new site I know nothing about, I cancel all script behavior. This turns off all animations and flash, but lets me read the web content.
In tube sites, like youtube, which are known to be safe, I allow scripts and enjoy the FLV movies! So, enjoy but dont let the monsters inside.