vista & hd's - no boot :(

My cousin wanted to get xp installed on his vista machine (2 sata drives, we were going to use the one without vista, ovbiously), since we wanted to be sure we weren't installing xp to the vista drive we unplugged it, tested the boot and it failed - which is fine, because the non-vista drive has nothing on it, so it can't boot.

When we selected the only partition on the xp install screen it warned us about the drive/partition having another system's data on it, we thought that meant we unplugged the wrong HD.. So we plugged them both back in and then we were getting a "verifying DMI pool" thing at boot, we tried all boot configurations and tried booting to each drive individually (because we weren't sure which was vista) -no luck.

NOTE: We turned off the power every time we unplugged a drive - which I now realize doesn't really help - so it might be a bios thing? (prolly not, because we tried all the configurations, and loaded the "fail safe defaults" and the "optimized defaults", though never found a reset bios option)

Now I added a jumper to the vista HD and it booted into recovery, this made C:\ change to D:\ and D:\ change to C:\ (C:\ and D:\ are separate partitions on the vista drive, d:\ is recovery), but for some reason we can't even access the recovery options from the advanced options on 'Computer' (that would be 'My Computer' on XP).

If you want to dual boot you would need to leave the other hard drive in place. Boot.ini gets modified on the primary drive to give you the option of booting from each OS.

We hadn't installed XP yet though, we're just trying to boot into the original vista, all we can do now is go into the recovery backup. And there is no boot.ini on the original vista partitions root.

There is no boot.ini in Vista. Vista uses BCD/BCDEDIT ( google it up )
When you recover Vista look at the links below
Here are some links on installing XP on Vista
http://apcmag.com/how_to_dual_boot_vista_and_xp_with_vista_installed_first__the_stepbystep_guide.htm
http://www.howtogeek.com/howto/windows-vista/install-windows-xp-on-your-pre-installed-windows-vista-computer/

http://forums.techguy.org/windows-vista/558994-how-install-xp-after-vista.html

EDIT: You did plug the HD's back into there original SATA ports ?
Sound like the drive with nothing on it may have had a hidden partition (recovery?)

In the Bios settings there is some times a HD boot order.
The BIOS reset is a jumper on the mainboard and can destroy the motherboard if you mess with it when the power is on

We never tried to reset the bios jumper, we tried changing the physical drive order and changing it in the bios, now all we can do is boot into recovery.

Is that the command line console or is it Windows Safe mode?

No, apparently when geek squad did the computer for him they put a backup to the first vista install and named it recovery. No it is not Safe mode, we're currently reinstalling vista on his second drive, if we can't figure out how to boot into the original vista we're just going to copy over his stuff from the original to the secondary drive.

If your installing Vista from an orginal Vista install disk you could have tried the recovery console and use Bootrec.exe http://support.microsoft.com/kb/927392

BLAST! thats what I saw around 4 hours before we got into the recovery console, by then I completely forgot what it was called and forgot what I searched for to find it!

He settled for copying over the files on the original, which wasn't much of a problem seeing as he barely installed anything.

A word to the wise.
Before attempting any thing that can make a mess of a system, google it with the right words/phrase. You may get lucky as someone my have already tried it, and it could save you from digging your self into a deeper hole.