In that case, if you just want an MP3player, use WinAMP, it's fairly light when it comes to system resources.
But if you want to do a whole bunch of cool things in addition to playing music, Jukebox will let you burn mp3s into .wma, .cda, (or other formats) directly to the CD-R without having to convert them yourself. It does a whole buncha other neat things too....try it out.
Oh, but winamp also lets you play 'Astroids'.
Check out Britney Spears' (o)(o) <A HREF="http://www.geocities.com/stick_e_mouse" target="_new">hooters</A>!!!