Below you can read my efforts to add Windows Vista to my setup. I wrote it to share my experiences. I realize that there is a large Windows content in this post. From regular reading of the Mint Forum I gather that multi system booting is a constant source of need for tweaking. I hope that this post can help others.
Read, shiver and learn. Please do not react with Microsoft / Windows bashing, we all know that Windows does not care for non-Windows systems!
My setup before I started was: two ATA hard disks, first HD first partition Windows XP, 2nd HD 3rd partition Linux Mint. GRUB is the bootmanager.
I added a third ATA hard disk to test drive Windows Vista. In BIOS terms: Prim Master: first hard disk, Prim Slave: DVD Writer; Sec Master: the 2nd hard disk, Sec Slave: the 3rd hard disk.
Vista was happy to be installed to the 3rd hard disk. I was curious to see what would happen during booting. Well, GRUB was gone of course, replaced by Vista bootmenu which showed 2 entries: Vista and XP. Restoring GRUB was easy with the Mint Live CD. See elsewhere on this forum for instructions.
The GRUB menu still showed the Windows XP entry. Selecting that led to the Vista bootmenu, with XP and Vista as choices.
So far so good.
Now I wanted a clean boot menu: either all three choices in GRUB or in Vista's boot menu. And that is why I wrote this: That was not trivial. I checked on the Internet and found several helpful documents. The straightforward options did not work, i.e. adding Vista to GRUB because there was no boot loader on the third hard disk (hdd or hd(2,0) in GRUB terms).
Adding Mint to the Vista boot menu with EasyBCD looked promising but also complex because and additional program NEOGRUB is required. (Windows complained that NTLDR was missing.)
I solved this challenge by opening the PC box, connecting the 3rd drive as primary master (DVD Writer as 2nd Slave) and using the Vista Boot startup repair options. I wanted the 3rd drive to be bootable. It took three repair actions and reboots to make Vista boot the disk, but that only took some time and perseverance and not efforts or intelligence to make that happen.
Then I switched the hard disks to the situation described above. I added the 'normal' Vista entry in GRUB:
title Windows Vista
By using the Recovery Console of Windows XP install CD I could clean up the XP boot process. Of course I had to re-install GRUB afterwards.