Errors ON HD Prevent Windows From Booting

If another working PC is available then use it to
connect sick HD as primary or secondary slave 
or secondary master.

If a working PC is NOT available then setup windows
on a different HD then connect sick HD as mentioned above.

Run scandisk on Sick HD.  Choose standard scan and fix
errors automatically. 

For Win95/98/ME:
If Errors are found choose to delete and skip undo.

After scandisk has completed run defrag too.