Apple or PC?

If you have read Kim’s tale of computer woe, you know we are looking for a new computer. I don’t want to launch a holy war of PC vs Apple, but what about a Mac Mini? I don’t know much about Apple hardware. The main requirements that we have are able to do our podcasts (good quality sound in/out, edit 1 – 2 hours audio without bogging down, affordable software to do so) play some games (good video card… Sims 2 for Fi and ? for me I like FPS). I can get a Dell for about the same price (I get a discount) and I’m certified with Dell equipment, so I know it can do what I want and I know I can upgrade. The thing is, I’m pretty sure the Mini can’t be upgraded (except for memory?) … I ‘spose if I want an upgradable Mac I gotta go with the G5 which starts at USD$1300. Too much when compared to PCs. Any suggestions?