Toshiba laptop will not start up! Error message!?

Hi guys! My wife is having a problem with her laptop which is a Toshiba Satellite C660 running Windows 7. It was working fine earlier, but out of the blue it decided to restart itself - or try to - but now it gets no further than the screen you see below:



After a bit of Googling i'm lead to believe it's something to do with the hard drive not being detected? I don't know, i'm not technical enough to understand this stuff. I found this video and removed and reinserted the hard drive (after blowing about inside) but no luck... that usually solves everything!

Please advise! Thanks for any help anyone can offer :)