I just got my m240 last week, and I am using Win2000, SP4. I’ve only tried MSC mode, and copying music files to and from the m240 like a flash drive. I haven’t yet any problems transferring files, having the m240 update its library, and playing music. I am still trying to figure out how to get tracks on an album to play back in order, but I don’t think that’s related to using Win2000.
A related question is if anyone has tried syncing the m240 via Windows Media Player 9 on Win2000. I know the m240 officially requires Media Player 10 and WinXP, but I’ve come across Sandisk documentation that implies that Media Player 9 is ok, which can be run on Win2000. I might fool around with it myself [if I have time!], but has if anyone else has tried it?