Reboot using the Windows ME startup disk, then select Minimal Boot. At the A:> prompt, type C: to go the C:\ prompt, then type:-
NOTE there is a gap between scanreg &/
and press Enter. Make sure you include the space between scanreg and the forward stroke. You'll then see five earlier Windows versions by date to restore from. Make your choice using the cursor keys (those marked Started are ready for use), press Enter and follow the on screen instructions to restore the registry to that version. Then restart to return to the desktop.