Formatting the drive is a last resort and before you do you must make sure you either have restore disks from your distributor or a full clean back up.

The Mac should be able to do everything a PC can with regards to moving files around, except the Mac leaves rubbish everywhere it goes! They are dirty devices.

The reason you can't see your MP3 files is likely because your mac has probably converted them for use in Itunes and they are pretty much unplayable on anything else.

If you are going to get PC - I would recommend a ThinkPad T or X series, they are rock solid and designed to work. I wouldn't trust my data on anything else. If your after a used one, a T61 is a super unit (and will runs Windows XP or 7 Easily - Vista is yukky, avoid it) you should pick one up for under £150, otherwise an X60 or X60s for the same price but much smaller and lighter (but no built in CD/DVD drive)

If I were you i would run the checksum tests before you do anything and clean out all the rubbish your mac has left all over the place!