Why does everyone in the IT industry get so wound up by the difference between a Mac and PC?

I am about to buy a new computer for my home. I need it to surf the web, check mails, write letters (and use spreadsheets, do the odd presentations), watch the occasional film and store my photos and music and that's about it.

I've owned Dell, Toshiba, Compaq and HP computers. I am fed up of computers that take ages to fire up, crash and generally take shed loads of maintenance to just keep running. So I'm plumping for a Mac. I'm reckoning that the "TCO" will be significantly better. If not, I'll buy something else next time around.

Ergo, these are not apples and pears. if Apple make computers that mean that buyers get what they want, they'll grow their business.