I use Kerio Firewall, AVG Anti Virus, Trojan Hunter, SpyBot, AdAware and Spysweeper. I had Pest Patrol on the old computer, but haven't gotten around to installing it yet on the new box.
When I run various security tests, I pass them all. Which of course doesn't mean I'm totally protected, but I feel pretty good about the software I use.
Btw, 20 years ago I would have been at the Tip A Few.