Moms' Laptop

Hello,
My mother got a Laptop from me.
It is the HP Pavilion dv7-1240us. She asked me to see what I could do. She gave me the unit;
heres whats going on.

the unit was working just fine, then she powered up the other day, and nothing just Lights on the KeyBoard face..HD light on too;
There is nothing on the screen.,,at all. "Black" not blue.
Just to add' don't know if it matters but I put in my windows cd, booted up heard alot but nothing showing up on screen.
CD - ROM running, so then I let the battery die.. recharged and tried to boot samething.
So, My mom took it to BestBuy GeekSquad... they said around 2 to 300 to fix it but didn't tell her what was wrong.. HHHUUMMM ??
Money??? maybe something simple, but they see Dollar signs and a women they can take advantage of..
MAKEs ME SICK..

Any ideas,??
Thanks to people like you and your Knowledge.. Dominic