Can I use DVD-ROM to upgrade a CD-ROM installed Office 2000?
No. In order to add new features or reinstall Office 2000, you need to use the same disc you used for the original install. For example, if you used a MSDN CD-ROM, you must use the same CD-ROM. The MSDN Office 2000 DVD-ROM will not work in this case – to use the DVD-ROM version you must first uninstall the CD-ROM version, then reinstall using the DVD-ROM.