Originally Answered: Mac vs. PC; which would you choose and why?
It would depend on what my goal is.
If I'm looking for a "gaming rig" I would choose PC. Most games are still written with Windows and DIrectX in mind. If only they would use OpenGL the games could be easy to port. It's much easier to get 3D Acceleration cards working with Windows (In my experience).
If I'm looking for a "Business machine" I would choose PC. Macs are fully capable of editing spreadsheets, word processing, etc. In fact, they use the same tools as the Windows machines use. (It's all microsoft in the end!) This is mainly because most people use PCs. Also, you can get a dirt-cheap PC to turn into a business machine. While you can get a Mac Mini for that purpose (for about the same price), you have very limited upgrade oppertunities with a Mini... whereas you could completely upgrade this "Business PC" to a "Gamers Rig," should you desire.
For security... MAC and PC. Yes, that's right! Macs are excellent in this department. They run a version of BSD (Unix) that's quite secure. Also, Apple has a name in security they have to keep clear, so they're keeping ahead of the curve. Windows have given the Intel/PC archetecture a bad name... however, a PC running Linux (or even BSD) can be just as secure as a Mac.
For Art... MAC all the way. I use Photoshop and Illustrator on both Windows and Mac in my dayjob, and I find the Mac versions of these softwares to be much more stable than their PC counterparts. They seem faster and more reliable. The memory access seems faster for large files... etc.
For programming... PC. I've used both PCs and Macs for development, and I simply prefer PCs. Mac development programs tend to be TOO user friendly for my taste. However, this is more of an opinion than a fact, as I use the same tools (gcc, etc) on both PC (linux) and Mac (BSD).
One point to make clear in your paper on the debate is that the debate is between Mac/Mac OS X and PC/Windows. Modern Macs are made of the same parts as PCs. They have the same processors. They can use the same operating systems (BSD, Linux, BootCamp Windows, etc).
As an operating system, I prefer OS X BSD over Windows any day. However, I prefer "Ubuntu Linux/PC" for my computing needs.