QUOTE(cambiata @ Feb 7 2009, 04:51 PM)

Does that mean then that my computer keeps crashing simply because it is a PC? I thought there was something specifically wrong with my machine - like the hard drive wearing out or something

Not exactly. Its just that with a PC there are so many things that can go wrong, and worse still, you never get to the bottom of why. Is it the hardware, the software, the graphics card, the sound card etc. With a Mac, they are all made by the same people.
Hard drives should not wear out unless they are quite old or under very heavy constant use, PC or Mac.