You have somehow overwritten the Vista boot loader on your internal HD with the GRUB boot sector. This would not, normally, be a problem, but the GRUB boot sector you've installed is looking for it's second-stage files on the removable drive, so you can not boot without your USB drive plugged in.
If your laptop has a typical Vista installation, it should have a "recovery" partition on the internal HD. If you can boot that partition, you can restore the Vista MBR to your internal HD. You should be able to force a boot from the recovery partition after you get the "Error 17" message by using the GRUB editor to modify the Vista boot instructions. (The GRUB editor just uses the keyboard arrow, home, end, and backspace keys to edit the boot instructions in memory. I doesn't make any changes in the boot configuration file.)
Anyhow, get to the place where you were ready to press enter to boot Vista. At the bottom of the screen you should see a block of text describing how you can edit the boot instructions. After you read them, press the "e" key to open the instructions for editing. You should see a block of text similar to this:
Code:
rootnoverify (hd0,0)
savedefault
makeactive
chainloader +1
Select the
root line, press "e" again, and change the
(hd0,0) to
(hd1,1), press enter to save the change, then "b" to boot from the change instructions. F.Y.I.: GRUB numbers drive and partitions from 0, so (hd0,0) means "first partition on the first drive" and "(hd1,1)" means "second partition on the second drive." Since you've booted from the USB drive, that drive is the first drive, and the internal drive is the second drive. One problem with GRUB is that the drive numbering can depend what the BIOS uses as the boot drive.
Anyhow, if my guess is correct, that should boot you into the "Rescue" miniNT OS where you should be able to restore the MBR so Vista will boot when you don't have the the USB drive plugged in. (By the way, using
(hd1,0) instead of
(hd1,1) should boot your Vista for you, but I don't think you can restore the MBR from inside Vista.)
After all that, unplug the USB drive and see if you can boot Vista. If you can, then all that needs to be done is to install a GRUB MBR on the USB drive and fix the
/boot/grub/menu.lst file on the USB drive so you can get into Ubuntu or Vista when you boot from the USB drive.
That should be fairly easy, but let's wait 'till you've got your laptop back to the state it was in before you started playing with the USB drive.
Try the above, and post your results.
