Unable to load Windows XP

On starting up my Compaq PC, I receive Norton GoBack (NGB - version 4.20.10) error message 141 saying that the machine needs to reboot. On clicking "Yes", after a while I receive error message 122 as follows:

 

"NGB rebooted your computer because it detected your system was unstable. Allowing it to continue running would have caused corruption on disk no 1. this instability is probably the result of a bug in an application running on your system, but could also be caused by hardware problems. NGB will now scan your disk to verify integrity of its data. When Windows loads, you should run ScanDisk (if it doesn't automatically run by itself)."

 

It then attempts to load Windows XP but fails to do so and the whole cycle starts again.

 

Has my PC  totally crashed or are there any remedies available for me to try short of a total rebuild? Many thanks. 

 

(I suspect if it is a bug that caused this problem this must have come from responding to what looked like a genuine invitation from HP to download updates to my 3-in-1 printer, which Norton Internet Protection failed to catch.)