Media Player 9 is the latest version Windows 2000 can run. I haven't upgraded to XP (and don't plan to). The files are MP3 files, but the problem is not with the files, it's with the licenses. I downloaded from WalMart (yes, I even shop there on-line) and can't get the "security upgrade" to take. Windows Media Player will not play the files without the license, and I can't get the license without the upgrade.
I didn't know it was possible to apply Digital Rights Management to an MP3 file.