This is a dangerous debate to get started on but...you should get a Mac.
I spend most of my week suffering with PCs. when I get home I use Macs. Why? because they WORK. I don't have to worry about locating some obscure drivers, bad inits or whatever. I turn it on and can enjoy using the nachine to help me accomplish what I want without getting in the way. OS 10 has crashed exactly once in four months(on three computers) and the new laptops are fast and can easily replace a desktop.
For genaral use the ibook 14" is a great machine, for more intense work gat the titanium 800 Mhz.
If you do digital photgrapy i-photo will satisfy most users (included), if you want to do video i-move is great (included), for MP3's i-tunes works very well (included).