You could try a repair installation which should (hopefully) leave your data untouched.

Boot into the Windows 2000 installation CD
Press ENTER ("To set up Windows now")
Press F8 to accept the License Agreement

If Windows Setup can find an existing Windows 2000 installation on your hard drive you will be given the opportunity to repair it.

Press R to do this.
Then just follow the prompts. Windows 2000 will appear to be installing itself for the first time, but it will (hopefully) retain all your data and settings.

I guess you should make sure you have your CD key handy just in case it asks for it.

The answer no, you can not reinstall an operating system without data removal, otherwise for data purposes, you can run the installation over itself (this will damage the registry), but will allow operation enough to save it until you perform a clean install. I would recommend backing all data up to other media (CD disks or DVD disks) then formatting and reinstalling 2000. It would be a cleaner option this way.

You run the repair mode from the 2000 cd. Once completed it will remane files and change them to either .old or use a tilde (~) character for file renaming (which you will have to check those files as to ones you may want to save.

Thank You,

How would I run the installation over itself?  That is what I want to do. 

I want to try and recover what I can and then run a clean install.  Thank You.

Q