Comprehensive Comparison between Mac and PC?

I have been a Windows user all my life, and I’ve had a lot of bad experiences. I’m seriously considering getting a Mac as my next computer, but I still have some doubts. I’ve looked through lots of statistics and consumer comparison charts and all that, but I’d like to hear from people who have extensively used both. Any input would be helpful. But specifically, I’m looking for comparisons in the following areas:

1. Malware vulnerability – I’ve had lots of run-ins with malware and I’ve heard that Macs basically don’t get viruses.

2. CAD functionality – because I’m an engineer and whatever computer I get needs to be able to run PRO-E or the like.

3. Battery Life – self explanatory
and last but not least,

4. Gaming functionality – . . .because I’m addicted to WoW. . .