My reccomendations: Throwing tools at your PC in hopes that they'll stop everything is futile, since they're always two steps behind what's out there. It's much better to have a method of preventative maintenance by using more secure programs and less risky PC use.

For example, use Firefox instead of IE. Use Google to do all of your searches, since it has a built-in filter to prevent people from going to reported attack sites. Don't use MSN, AIM, or YM clients, which tend to be exploited to send viruses - use a client like Trillian or Pidgin, which have a lower chance of being used for attacks. If you use P2P apps like Soulseek, never, ever ever ever ever download any .exe file, ever. And of course be wary of any e-mail attachment, ever, if it's an .exe (many e-mail clients won't even let you open it). From there you should have regularly scheduled antivirus and spyware scans.

I didn't use a firewall for years when I was on Windows, but by using more secure programs I was able to avoid problems. Also, gonna move this to Help.