I have a simular problem with my Windows ME not booting from GRUB, which I'm trying to sort out.
Does your mobo have the facility to press F8 at boot-up, and select which drive to boot from?
Also, does GRUB or Linux not see your SATA drive as a 'sda' drive?
If you have F8 facility, then for the present you can boot into windows that way, until your problem is sorted out.
Also, what make of PC have you got?
If it's something like DELL, then I believe you have a BIG problem.
When I find out how to get over my problem, (Error 25), then I will let you know the answer. It may help you with your problem.