This isn’t Mac Vs. PC, its Mac OS X vs. Windows. Get that straight. You can run both operating systems on both sets of hardware, flawlessly.
Mac is good for some things, such as design, web developement, video editing, basically anything multimedia related mac does better.
Windows is good for games. Which is really all that NEEDS to be said for Windows.
If it means anything, this entire site was designed on the Mac platform. A Macbook Pro to be specific.