Here is how I fixed it - whole thing took 2 minutes.
An important point that cmdr linked to in his post applies only if you're moving a Windows system partition. I quote,
"You simply have to delete ONE Registry key BEFORE you use "GParted":
(Start - Run "regedit" - Search "mounteddevices"- Delete whole key)
NOTE: BE SURE, NOT TO ALTER ANYTHING ELSE, THERE IS NO "UNDO" !
Don't worry, this Registry key regenerates "slim"
(not connected drives have gone) on next boot. If you changed drive
letter assignment before, i.e. "renamed" a drive to a new drive letter,
this has also gone afterwards. Drives are redetected and "named" in
AVOID RUNNING INTO NEW TROUBLE : DO NOT CONNECT (ON ONE
SYSTEM) SOURCE DRIVE AND TARGET DRIVE OF A CLONED PAIR
SIMULTANEOUSLY OR SEQUENTIALLY, IF YOU RUN WINDOWS.
Duplicate Drive IDs are not allowed under Windows !
You MUST change one ID at least (HowTo below !)."
With that out of the way, here is what I did. Remember my disk layout:
It has three partitions on it currently:
/dev/sda1 is NTFS and contains Windows XP
/dev/sda2 is NTFS and contains a large data partition
/dev/sda3 is ext3 and contains my /boot for LINUX
(LINUX stuff resides on a 2nd smaller HDD).
Booted to a live CD (ubuntu has a nice one)
$ sudo mount /dev/sda3 /mnt
$ sudo grub
<<from within grub>>
> root (hd0,2)
> setup (hd0)
$ sudo umount /dev/sda3
$ sudo reboot
If you have more questions, see this article which I'll quote below in case it gets removed.
HOWTO Restore GRUB
You have windows 98 and linux on the same hard disk and you choose GRUB as boot loader.At boot time you see a menu to choose windows or linux.
But one day you reinstall windows 98 and it rewrites your MBR and the menu has gone, now you only can boot windows.
What to do:
Put the redhat boot disk you created on the installation on the floppy drive, boot the system and run grub command
Remember that for grub (hd0,1) means hda (primary controller master), second partition.
Now we need to tell grub where are the grub files:
If you know where they are, type something like:
else if you have no idea, type:
and then the root command with the correct parameters:
to install it on hd0, that is MBR of the first HD.
type quit and reboot.
The menu will appear again.