This is a problem when Windows is running some malware that cannot be removed, which happens all the time. The problem is all the new hardware or specialized hardware will not work on Linux so Windows is the only choice. I would think the latest versions of Linux would have this problem worked out by now. I installed 11.3 one week ago, only to find that the repair option in the install menu no longer exists so don’t bother uses this link to reload the GRUB HowTo Boot into openSUSE when it won’t Boot from the Grub Code on the Hard Drive. I also tried this link Re-Install Grub Quickly with Parted Magic which does not work either. On step 2 typing grub returns the error message “grub command not found”. You can use GRUB if you boot the install DVD and select Rescue Boot. However when you type find /boot/grub/menu.lst the error message “file not found” is returned.
I did the following to restore my GRUB boot record. Boot the install DVD and select the update option during installation. Change all the repositories to enable except the NVIDIA repository, it is not responding at this time. When the system comes up go into Yast and open the boot loader. It should have your original boot menu in memory. Change the default to another option and re-write the MBR. This will write a new MBR using the original data updated with your new default. Re-boot and then change your default back. I am just a NewBe so this may not be exactly correct but I hope it saves someone like me some time fixing a MBR re-writing by the Windows installer.