bjobie

If it's just shutting off, it's probably not your hard drive. Since it charges intermittently it sounds like it isn't charging your battery and not effectively powering the laptop. So I'm saying it's the dc-jack. Which can be part of the motherboard, but sometimes it's a separate part. Either way, you dropped it and you're having problems that don't really point to a part other than the board. Even if you replace the dc-in jack, there might be mini-fractures on the board which can cause havoc with integrated circuits. I'd pull the hard drive, back up the data, and sell it on ebay for parts.