Gateway netbook turns on then goes to a black screen

Hello,
my gateway netbook was fine when i was using it then all of a sudden it shut down on me. i thought it was the battery at first but the netbook itself was fully charged. i left it alone for a good couple of months to see if it will turn on and it does but as soon as it gets to the welcome sign like most laptops do it goes straight to a black screen. i can see the mouse perfectly but when i move it and click on buttons it doesnt do anything but stays on the black screen. can someone please tell me what might be wrong. i have to use my brothers laptop but would like to continue using mine. please tell me whats wrong with it. thank you much appreciated