Does anyone know of any software that could back up my MP3 files "randomly"
so that each disk is mixed for playing.

Currently your choices are alphabetically, file size, date etc.
I have 11 Gig of music and want to use my back-ups to play in my car, thats why I prefer them mixed. Also can anyone recommend a good, stable, multi disk recording software. I currently use Nero and have tried Music Match but my computer goes into a melt down a freezes when I try to back-up 11 Gig of music.
Much appreciated.