I've been playing "FUN with partitions"  and I think I'm in over my head. Can I recover my XP partition and if so how would I go about it?

Situation:
I have two physical disks. On my SATA drive I installed Windows XP. After that, I installed Ubuntu 8.04 on an old IDE drive. Next, I installed the first Win7 beta, also on the IDE drive. I then re-installed Ubuntu to repair GRUB.

Up to this point, everything is working fine. Through GRUB I can choose Ubuntu or Windows bootloader, and if I choose Windows, I have the option of Windows 7 or Older Windows (XP).

As you know the WIN7 beta is ending, so I installed WIN7 RC1 in the same spot, erasing the partition I was using for WIN7. In order to do this, I had to physically disconnect the SATA drive to avoid an error I was getting during install. The SATA drive is now reconnected.

At this time I can boot into WIN7 or Ubuntu, but XP is absent. If I physically disconnect the IDE drive, I get a GRUB error (error 22) and am forced to restart. Looking back, I could have predicted an issue with this latest change,  but it's done now. I'm mostly interested in this as a learning experience at this point.    All OS's are 64-bit.

Options, explanations and constructive scoldings are welcome.
Thanks!

[Resolution:] Using the XP install CD, I chose the repair option which takes you to a command line. Typing 'help' displays the list of commands.  I chose FIXBOOT which did not seem to affect anything and rebooted.  No change. I repeated the repair process, but chose this time fixmbr.  I was given warnings that I may lose all data and partitions on the disk, but agreed.  Again there was no immediate effect. On reboot, I was greeted with my Windows XP load screen and now I have a working XP partition.  Thanks to Patio for a great answer. I would SIMPLY USE the BIOS to switch between which drive i wanted to boot to....
Simple and clean.

If this solution does not work then you will have to boot to the XP CD and choose R in the first screen to enter the Recovery Console.
This will load a command prompt screen...at the prompt type fixboot and hit Enter...
Remove the CD and re-boot.
If this does not work repeat the above except this time type fixmbr and hit Enter...
Again remove the CD and re-boot...
Keep us posted.Resolved
Patio,  that is exactly the right answer.  After repairing the XP installation using first fixboot with no discernible effect and then fixmbr I have my XP again!  Now I can change the boot order to get the OS I want as you suggested. Thanks!

One lesson down, 6 bazillion to go. I'll be here...maybe not for all 6 bazillion though...

Glad to hear you are fixed up. Quote from: patio on July 01, 2009, 10:07:47 PM

I'll be here...maybe not for all 6 bazillion though...

Glad to hear you are fixed up.