My screen won't turn on and my battery doesn't work

Okay, so, my laptop is such a pain at the moment! I can't turn it on unless it has the power cord but that isn't the only problem! I try to turn it on and it works but the screen doesn't. I heard the 'hold button for 60 seconds take battery out and power' method but it doesn't work because I have to have the power cord in. It is really annoying me because I have alot of memories on this laptop like my (passed away) cat. Please help me. I can't take it to the computer shop because it is my mums and she won't do anything about it!!