lost bootup to desktop

[nepal]

I had a power cut today while Kubuntu 7.10 was up and 
running. When I try to boot the pc, I see the Kubuntu 
loading screen with the blue progress bar for a few seconds 
then I get a black screen with just a flashing cursor in 
the top corner. No x seems to be loaded, I can do nothing 
at this point except reboot with Ctrl+Alt+Del. Ctrl+Alt+BS 
does nothing. Is my system screwed or is it possible to get 
it back up and running.

Note I have/had Nvidia drivers installed. 

Can anyone advise please?

TIA

nepal