Copied from another form. May help.
If you've got your Windows 2000 install on a separate partition, the removal is fairly routine.
Simply boot into XP and delete the (eg) D:\WINNT folder.
Then remove the reference to the windows 2000 install on the C:\BOOT.INI file -
multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows 2000 Professional" /fastdetect
**MAKING SURE THAT XP IS THE DEFAULT OS**
You can then remove the WINNT remnants, such as SVI and the user folders., or simply format the partition, since any programs installed under Windows 2000 will be obsolete.
If you've got the Windows 2000 install on the same partition as your XP install, it's slightly different. Initially, try deleting the C:\WINNT folder after booting into XP. It may not allow you to do so, as there may be XP system files referenced within C:\WINNT.
If this is the case, the easiest wasy to delete the C:\WINNT folder
is to boot into DOS using a Windows 9x Start-up disk, and delete it from there. Restart and boot into XP (you should still be given OS options at this point).
Again, edit the boot.ini file from within XP, ensuring XP is the default OS.
At this point, depending on how you configured the dual boot layout, you may find that the user files are common or shared between XP & 2000. If this is the case, you'll have to manually weed out the Windows 2000 files and folders no longer needed, such as 2000's start menu, application data, etc.
The SVI -System Volume Information - folder will probably be shared between the OS's, and if this is the case, just leave it.
If there are two SVI folders, you may run into trouble deleting the old, unneeded Windows 2000 one. If you have any bother with it, such as being denied access to it etc, right-click on it and click the Sharing tab, and check the 'share this folder' box, calling the folder SVI to allow network shares. Then you can -in theory, delete it as well.
