Why is my Dell laptop screen not working?

About a month ago, my Dell Studio 1535 laptop (2008) took a hard beating which tore off a bit of the plastic casing around the screen and broke the backlight. Nothing else was harmed. Odd. About two weeks ago, I got it back and it was working properly again, up until now.

When I try to start up the laptop, it displays a blank, backlit screen, and the computer itself seems to be otherwise working and starting up properly. This is the second time ever, and second time today, that I’ve been having this problem, and I was able to fix it on the first try by, ahem, mashing random keys with my entire hands back and forth, and after about 3 minutes of that, I saw my computer loading data or whatever in order to start in safe mode. I restarted the computer again, and it worked normally, until I shut it down again and tried to start it back up right now.

Running Vista, Intel processor, and Intel chipset for graphics.

Oh, and hello again, Fluther! It’s been, like, half a year. Did anyone miss me? :3