Eventually, you will have to perform Windows 2000 registry maintenance. Here’s an article on how to back up, edit, and restore the registry in Windows 2000.
The most important thing you will have to do is to make sure you can revert your changes back to the original state of the registry. The best way to do that is to have an export of what was changed and be able to import the changes back into the registry. In this manner, it would be like nothing ever happened. From the article:
Before you edit the registry, export the keys in the registry that you plan to edit, or back up the whole registry. If a problem occurs, you can then follow the steps in the “How to restore the registry” section of this article to restore the registry to its previous state.
Microsoft KBA 322755
How to back up, edit, and restore the registry in Windows 2000