As someone who has a PC and an iMac sitting side by side on the desk, let me advise you to run whichever system you feel the most comfortable with. I like the iMac, but for the money I spent on it, I could have purchased a lot more PC processing power. The iMac appears stable, but when I rotate into the next computer upgrade (read when I can
afford to make an upgrade that is already 12 months past due), I will not be purchasing any more Apple products.
If you fall for the trap that Apple's do not and can not get virii, I have a bridge in Brooklyn for sale. As the Mac products increase their market share, the crackers will become more interested in writing Mac exploits than they already have been.
Apple: Mac users should run multiple anti-virus | Zero Day | ZDNet.com
Apple Quietly Admits Macs Get Viruses
If you want to feel protection from virii because of the particular Operating System you use, my recommendation is to install a Linux distro on your PC and save your money. One of the more stable and more supported Linux offerings is also available for the low cost of absolutely nothing -
What is Ubuntu? | Ubuntu
Some Windoze users cringe at the thought of trying to use a Linux distro because they do not want to learn to use a command line prompt. Let me tell you, those days are over. If you're worried about learning a new OS, you're going to do that with a Mac anyway. And the latest and greatest Mac OS, Snow Leopard, is actually evolving from Linux anyway, so what is the real difference? Well, a 20" iMac is going for about $1200 and Ubuntu is free, so you do the math.
Take a look at the features in Ubuntu -
Features | Ubuntu Desktop Edition You can download Ubuntu for free, burn it to a CD-ROM and test it out for yourself without having to install it. It will run rather slow since you are swapping everything within the OS in off the CD, but it will let you see how simple Linux has become in the last few years.
If the idea of installing an OS scares you off, look into Wubi -
Wubi - Ubuntu Installer for Windows A Wubi install isn't quite as sleek and spiffy as a standard Ubuntu install, but most of you will never notice the difference.
If you don't like Ubuntu, look into openSUSE, Mint, Fedora, Mandriva, Sabayon or any of the other available distros -
DistroWatch.com: Put the fun back into computing. Use Linux, BSD.
For the record, this box is a Dell XPS PC, dual-booting Windows Ex-Pee and Ubuntu 9.04, a.k.a. Jaunty Jackalope. Sitting right next door is an iMac running OS X Snow Leopard and Windoze Ex-Pee under Parallels. In the great room is a PC running Ubuntu 7.10, a.k.a. Gutsy Gibbon. None of these boxes has ever come down with so much as a sniffle, not matter which OS I am running. Two Computers, four operating systems, five Web browsers and one e-mail client with a total of twenty-one e-mail addresses. Two of the computers have no add-on virus protection whatsoever, outside what is native to the OS. I've been online for 28 years with all manner of computers and operating systems. The number of virii any of those systems has come down with? Zero.
I know you Mac users would all rather fight than switch and I support that. But as for myself, I don't need to defend the iMac (or the Snow Leopard update) simply because of all the money I spent on it. It's a smart-looking and very solidly-built computer, but beyond that it leaves me cold.
I will admit to being an old dog and maybe I am just resistant to new tricks, but then again, aren't tricks for kids?
The best virus protection scheme available is the one between your ears. Be smart and you'll never have trouble with a virus. Open every forwarded e-mail that has an attachment you simply have to view and you'll be plagued with problems the rest of your life.
, but I am really glad to see that it is only your computer that did the crashing. 
