my son runs a 133 mhz Gateway Pentium with win95 and 48megs of memory, and has a thousand MP3's that he listens to without any problems.
he also does IM, surfs etc at the same time without difficulty.
where people come up with the idea that "slower" computers cannot provide contemporary functionality baffles me ( is suspect those people are exclusively teenagers - experts without experience)
there is NOTHING that a P133 cannot do with the exception of "gaming"
my son runs soundforge, photoshop, wordperfect, etc without any difficulty.
now, i like a fast computer just like the next person..but if you are a tightwad like i am, you hate to waste a perfectly functional computer..
good luck with your purchase - you should be able to get lots of use out of it. my advice would be to stick some more memory in it (but actually not required!) win 95 if fine, and you can pick up a 10 gig hard drive for cheap cheap cheap, and this should be plenty for storing MP3's (about 2500 tracks or 200 albums). you will have to break the drive down into 2 gig partions with win95 - but don't worry - it works.