Options that come to mind.
1)
Do a parallel install as:
c:\temp-winnt-t
Do it via the 3 floppies (or a CD boot if allowed).
It will do several things:
It will rewrite the NT boot files completely; it will set itself as default OS to boot; it will add itself to the boot.ini/menu. It will also present you with a fresh Admin login (for this 'temp' version). Leave the passsword blank - this isn't going to be around very long... - and boot through to it. Reset default OS to boot to original version - and reboot - hopefully OK?
Once in OK, locate and remove C:\temp\winnt-t from drive; also edit out the 2 line reference to it in the boot.ini.
Job done?
The two routes below also usually work when attempting to restore damaged boot/start-up files.
A) Start a new install - and choose either an Upgrade of present installation; or even a Repair. (A Repair can be done without the ERD - at least at the level you are needing.)
Perhaps go for the Upgrade? At first reboot, stop the process, remove all discs and reboot - hopefully OK to original version.
B) Start as before and choose Repair; allow it to Repair the installation - without an ERD...
You may need to re-apply any SP you have running going via the Repair route; not totally sure about that via a Repair (in toto). Going the Upgrade route, and interrupting it shouldn't require the SP afterwards. Going a full Upgrade (no interrupting it) will probably require the SP afterwards.
More than likely the 'interupted Upgrade' should do the job. Likewise even an 'interrupted C:\temp\winnt-t' approach; (i.e. interrupting the C:\temp install at first reboot - as in the Upgrade route) may also (will probably) resolve the problem.
If the interrupted approaches, and even a true Repair and/or Upgrade don't resolve it, then go the full parallel install (C:\temp\winnt-t). This should do it.
All of the above have been tried and tested (used) by folks various, here and other forums/fora. I picked up most of them elsewhere (http://www.zdnet.com/community and http://www.virtualdr.com) a while back.
They also usually work with W2K...
