SP4 = Windows 2000 Service Pack 4
Run
Windows Update (you must use IE for this). You may be way behind on updates so be prepared for some downloading and a few reboots. At this stage, all you really need is all the "critical" updates, SP4, and DirectX (9b). I hope you have a broadband Internet connection.
First off, I'll assume you've reverted back to MJ and that your running the latest version of Nero.
It could be that your library is corrupt. You might as well delete all the *.jmd files in the Data directory under the Media Jukebox directory (make sure MJ is not running). After doing so, start MJ up and see if it gets further. If it does, then re-import your media.
If you still have problems then uninstall Nero. Backup your MJ license (if you haven't done so) and uninstall it as well. Reboot and re-install.
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