As the description indicates, I have a terrible dilemma on my hands.
Just today, my trusty Compaq Presario v5000, a computer I have had for about 3 years just suddenly died.
I had just finally ordered some new hinges for the damn thing (because the pot metal is so brittle) when I was about to unplug the screen to settle them in. To my horror, as I pulled the cable out, something sparked near the base of the screen where the cable is nestled, that is, in the bottom right corner of the cable area (where the screen cable gets a little bit compressed naturally).
After this, I realized I still had the battery in. The thing is, though, I have disconnected the screen cable many, many times in the past without anything being set fire.
The heat sink was warm, but did not seem warmer than normal, but I still decided to check there first. So I took apart my laptop (it is outside of warranty) and cleaned out the heat sink and fan area. There was a lot of fine dust that could have caused an overheat, but I'm not sure.
Now my laptop will not power on or charge my battery. No power is being pushed through whatsoever when it is plugged in, and I already checked the power cables and connectors. Everything is set up to work, but nothing happens.
Fortunately, my little brother has the same computer make and model, so I was able to determine that neither my RAM nor hard drive were damaged by the effect.
So...what could it be? Can it be fixed without having to buy new parts? If not, what parts do I need to get my laptop working again?
Please help, as I use my laptop for everything, from my Yearbook class work, my two analytical papers and my music composition.

Here is the default HP FAQ:

Notebook Does Not Startup or Boot Displaying a Blank Screen

More general:

Startup and Boot ProblemsCompaq Presario V5000 CTO Notebook PC

If it were a display issue alone I'd suggest trying an external monitor. But you are saying you get no power at all?

Anyway try the tips in the first link.

No power at all. After the suggestions were attempted, nothing happened. Thank you, though.
Any other ideas what could be damaged?