Arrr, where's me patch, matey?

Most computer viruses attack vulnerabilites that have already been patched; they simply prey on the idiots who don't keep their software up to date. The funny thing is that there are also perfectly intelligent people who don't patch their OS and/or browser (the two biggest sources of critical security flaws).

I think the central issue is that, by and large, people don't realize that computers have not yet been dumbed down to the level of 'appliance'. In this respect they are analagous to cars: they can be operated by pretty much any idiot and can handle quite a bit of abuse, but if maintenance is totally neglected they can do some ugly things.

Whether we're talking about replacing brake pads or downloading patches, it is your responsibility to keep up on the maintenance of your equipment. I hate to get all catch-phrasey, but we share the information superhighway just as much as any physical road. Your spam-sending, virus-spreading, zombified computer is just as bad as that smoke-belching, no-taillight rattletrap you curse at as he cuts you off in traffic.

So, everybody, the moral of the story is simple: Keep your software up to date! To that end...

If you use Windows:
First, get Firefox. It's a solid, extensible browser that is also free (as-in-beer and as-in-speech).
Next, visit Windows Update. MS wants you to use their browser to get their OS updates, but you can point Firefox to WindizUpdate and get all the Windows patches you need!

If you use Mac OS or *nix:
Congrats, you are pretty dang secure (through obscurity) already! Stick with a distro/release that is recent enough to be supported with security updates, and you should be good to go.