You didn't mention the hive, if the software hive is corrupt, it may be
possible to rename the software hive found in;
%windir%\system32\config\software
to software.old
then copy the most recent backup found in
%windir%\repair\regback
as
%windir%\system32\config\software
If that fails you can copy/ use the file
%windir%\repair\software
This file is an image of the hive at the time the OS was installed, so you'd
have to reinstall all software. This being the case you might just as well
blow it away and start a new install. (note: this would at least allow you
to start the OS to make any necessary backups prior to wiping the drive.)
Else if the system hive, and assuming you already tried LKG, It may be
possible to rename the system hive found in
%windir%\system32\config\system
to system.old
then rename
%windir%\system32\config\system.alt
to
%windir%\system32\config\system
You can also try using the most recent backup found in
%windir%\repair\regback
If that fails you haven't much choice but to copy/ use the
original-as-installed system hive from
%windir%\repair\system
to
%windir%\system32\config\system
You'll need to reinstall the device drivers for any hardware added since the
original OS install.
To start the Recovery Console, start the computer from the Windows 2000
Setup CD or the Windows 2000 Setup floppy disks. If you do not have Setup
floppy disks and your computer cannot start from the Windows 2000 Setup CD,
use another Windows 2000-based computer to create the Setup floppy disks.
Press ENTER at the "Setup Notification" screen. Press R to repair a Windows
2000 installation, and then press C to use the Recovery Console. The
Recovery Console then prompts you for the administrator password. If you do
not have the correct password, Recovery Console does not allow access to the
computer. If an incorrect password is entered three times, the Recovery
Console quits and restarts the computer. Once the password has been
validated, you have full access to the Recovery Console, but limited access
to the hard disk. You can only access the following folders on your
computer: %systemroot% and %windir%
