Er... CPU requirements? Linux?
In the past I used an olde pentium (one!) 133 Mhz, 64 meg laptop as an mp3 player. A p2 or p3 with 256/512 megs is totally overkill, so trying Linux just because it'll run is like... er... well, not needed.
Just get a computer and OS that'll start up quickly. You could try older Windows versions or Linux if you want to.