PC unless you're doing some kind of video/photo/audio activities.
The PC has more problems for obvious reasons. When you have millions or billions of more people using PC than Mac, the PC is going to be a bigger target for viruses, the programming of the OS is simply more difficult, it requires more features seeing as how it's needed for use worldwide, etc.
People who aren't all too familiar with computers past the very basics would probably benefit more from a Mac, for the simple reason that you don't have to really care about malicious attacks, viruses, etc.