If you have an installation CD ( I have Mandrake 9.0 and 9.1) that you can make by downloading and burning the free linux ISO's, you can easily repair your MBR and LILO. Mandrake uses LILO by default. Doesn't matter if you have Mandrake installed, it will still repair LILO.
Anyway, set your BIOS to boot from the CD-ROM, insert the first installation CD.
At the first screen, press [enter] to install, or [F1] for more options.
[F1] takes you to a 'repair option' screen. You type 'rescue' then [Enter]
Now you will see options to repair LILO or simply restore a Windows MBR.
If you want to continue using your Linux, select the first option, of course.
This is apparently a common problem you have, this and finding a string of '99's when you boot up. Easy fix if you have the Linux installation CD's
And if you don't have Drive Image for back-up purposes, it's not like you will be reinstalling Windows everyday. You are now the master of LILO bootloader and the MBR.
Hope this helps
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