I just faced this problem a moment ago, I have removed my Linux Operating System(Ubuntu) from my partition where I applied dual boot Operating System previously.
Somehow, I were removed the partition through disk management from Windows Vista and the error as below found once rebooted the box.
If you get the same error and could like to removed Grub. Use the step as below.
1. Boot your box with Windows Vista Boot Disk.
2. Select the repair tools.
3. Select the console mode(Command Prompt).
4. Type this in the console.
5. Well done, reboot your box again and issue should be fixed.