When you reinstalled Win2K, did you do a fresh installation (i.e. wipe drive/start from scratch), or did you you do a repair installation?
I suspect you probably did the former.
Here is what I suspect is happening:
A System State backup will only work on the computer installation it was backed-up from. It is meant to repair Active Directory, not completely restore a DC.
Although you re-installed Win2K on the exact same computer with the same computer and domain names, as far as Windows and Active Directory are concerned, it is a different computer because it has a different SID. Since you applied the System State data from one installation to a different installation, Active Directory is probably confused beyond repair.
Your only hope will be if you have a complete (Full) backup of your previous installation.
If you do, restore from that backup and reboot. This will take your system to the state it was in as of the date of that backup. You could then apply the latest System State backup to bring it up to date.
If you don't have a full backup of your system available, I fear the only way out of your current situation will be to do a complete re-installation and start from scratch.
FYI, to cover all the bases and protect your self from having the same situation happen again, you need three things:
1. Current Emergency Repair Disk - updated whenever major hardware or software changes occur.
2. Regular, full backups of your Win2K installation - tobe applied when your server fails to the point you can't boot into Directory Services Repair mode.
3. Regular System State backups, to repair Active Directory if (when) it becomes corrupted.
