Screen went blank after windows update

Hello,
my computer was doing a windows update and i did not know it was not complete and I shut it down and closed my laptop. when I went to start it back up, I opened it and it was still on saying it was only 1% complete and not to shut down and then it shut down.I powered it back on and a bunch of numbers went acrossed it and then at the bottom it said enter f12 to reboot so I did. then the screen went blank and nothing happened. I powered it back off and went to work. I think something happened to Windows and I am not sure what to do. I think it was preinstalled and I do not have a disc.
It is windows Vista. Can you help me out?