Toshiba l300 disc recovery

I have a Toshiba satellite l300 laptop using vista. Recently, I try to start it up and I see the Microsoft loading bar appear, and then i get a large loading bar at the bottom of the screen saying 'windows is loading files'. From there it takes me to a grey screen with a pop up box saying windows32/drexe something or other and then disappears. I'm then left with they grey background and nothing happens. I've tried holding down 0 on start up and trying the f8 procedure but they do not work. Any other suggestions would be hugely appreciated! Many Thanks, Arron