Macbook pro has a white screen and is basically not allowing me to do anything.

My sisters macbook pro has a blank white/grey screen for some reason. We have been at school all day, we come home to find a small dent on the right of the trackpad, but the laptop had been closed all day. I have already looked at other peoples discussions talking about restarting and putting the Mac OS disc to reinstall and things like that... But the laptop is not allowing me to eject, or put anything in it. I have clicked on all different combination of buttons but still the white/grey screen. There is a disturbing whurring sound when the laptop starts up, almost like a small scratching noise and something has definetley been broken. I put the charger in and the small light goes orange teling us its not completley done for.

Has this happened to anyone else before?!

And we really need some HELP !! 😕😟