Okay try this, boot to the OS disc, choose the repair option (R), then choose (R) again to go to the Emergency Repair Process, When you do this, you see the two repair options:
Manual Repair
Fast Repair
Both the Manual Repair and Fast Repair options start by performing a system/boot partition file system check.
If you chose the manual Repair option, select the repair option by using the arrow keys. Use Enter to select or clear each check box.
[X] Inspect startup environment
Checks the ARC path in the boot.ini file for a path to the Windows 2000 boot partition and %SystemRoot% folder. If the Boot.ini file is missing, a new one is created with a valid ARC path.
[X] Verify Windows 2000 system files
Verifies that each file in the Windows 2000 system/boot partition is good and matches the files that were originally installed. This includes the Ntldr, Ntdetect.com, Arcsetup.exe, and Arcldr.exe files that are used for booting various computers.
[X] Inspect Boot Sector
Checks the MBR and fixes any problems. It will not remove MBR viruses.
Repairs the active system partition boot sector and reinstalls the boot loader functionality. If the partition uses the FAT or FAT32 file system and contains a non-Windows 2000 boot sector, this repair option also creates a new Bootsect.dos file to be used to dual-boot the PC.If you also select the Inspect Startup Environment option and a new Bootsect.dos file is created, Repair adds the following entry to the Boot.ini file: C:\ = "Microsoft Windows"
Should you choose Fast Repair, it will do all of those, but you are not prompted for choices.
Also the Fast Repair option tries to load each Windows 2000 registry file (SAM, SECURITY, SYSTEM, and SOFTWARE). If a registry file is damaged or cannot be loaded, Repair copies the missing or corrupted registry file from the %SystemRoot%\Repair folder to the %SystemRoot%\System32\Config folder