Ubuntu problem

Ok , so my brother downloaded Ubuntu at his school.
He got home and installed it on his laptop, and everything worked fine.
So i have a partioned harddrive where im gonna install linux. Ubuntu.
But I have now installed it and it doesnt work.
It starts in a none graphic mode ( its called something like that . I dont know :s ).
And I dont know the problem.
Everything should work fine but it doesnt …
Please help me if you can.