Computers are so susceptible to the user that it's unfair to judge either against the other in general terms.

Apples have their place... they simply work. That's what is so great about the iPhone and iPad is they just do what they do and they do it damn well. But you also pay Apple a premium for their name, older hardware, and locked down devices.

PC on the other hand offers much greater flexibility with significantly more variety in both hardware and software options (not talking about the App Store here - similar comparisons can be made, but currently the App Store blows anything Android has out of the water). Those perks come at the cost of compatibility issues that have to be ironed out by developers who may or may not have an interest in doing so.

I use PC because it allows me to build my own computers dirt cheap, and I enjoy having maximum control over my hardware and software. Apple doesn't allow me to do that. The only Apple device I own, my iPhone, is jailbroken for just that reason.

Also, virus protection is completely unnecessary for a savvy internet user. I have several machines and the only one I run AV on is my server (and it's just free AVG). A good hardware firewall can dance circles around system-resource-hogging AV software. I stick mostly to known websites (not that this is completely foolproof as any site could potentially be hacked), I am smart about the torrents that I download, and I typically use an encrypted browser (tor).