Dual Boot Problem

Alright, so I had this set-up:

Windows Vista, C:
Windows 7, A:
Recovery Partition, B:

For some reason, Windows had to move the default boot partition to C:, which does not have BootMGR. Because of this, my computer could not boot. I installed Linux Ubuntu Hardy Heron over C:, and have been trying to make it boot A: instead.

How could I do this?

Thanks,
Boon

Just to let you know, I can't open my Windows 7 folder. It says 'cannot mount Windows 7'.

If your just wanting to get back your windows 7 drive and aint to bothered about Ubuntu. You can just put your 7 disc back in and click 'Repair' and it will find any problems which would be missing boot file and re-create it for you and you'll be able to boot back into windows 7 and delete Ubuntu.

Clever me used MagicISO. :(