grub boot problem

[ktc0000]

I just installed ubuntu (dual-booting with Windows XP), and ive been installing necessary programs and such. i checked the "mark all upgrades" button in Synaptics and let ubuntu do its thing. after the updates were complete, i was chatting on empathy and all of the sudden i cant type....anywhere. cursor was basically useless. so i restarted my laptop, and lo and behold, the following message pops up and the boot process goes no farther:

error: no such device: 7dabc3ea-74c2-4a53-bba3-f60d6271ffd1.
grub rescue>

Im at quite a loss as to what to do next, and any help would be greatly appreciated. thanks

[oldfred]

Can you boot from the rescue mode?

https://help.ubuntu.com/community/Grub2#Command%20Line%20&%20Rescue%20Mode
Express Boot to the Most Recent Kernel
Command Summary ls to see drive X & partition Y (hdX,Y) or sdXY:
ls
set root=(hdX,Y)
linux /vmlinuz root=/dev/sdXY ro
initrd /initrd
boot

What partition is the error? From liveCD to see UUIDs:
sudo blkid

Did you edit any partitions before error appeared?