I like to protect myself from such Internet menaces as the Blaster worm by using a hardware firewall (mine is from Linksys). The nice thing about a hardware firewall is that it can't be reprogrammed into a menace, since the code is in read-only memory (unlike software firewalls). These firewalls are very easy to use and install and only run about $100, plus they have a useful router which lets me share my cable modem with up to four computers (more if I add a hub).

For virus pretection, I like Postini. This service ($1/month) blocks email viruses before they reach my computer. It also deals with spam, very effectively. And the Postini people deal with updating virus and spam profiles, not me.

The idea is to block these menaces before they reach my computer. Then computer configuration doesn't matter.