Serious issue with MacBook internet connectivity

I have owned a 2009 MacBook since around 2011, when I bought it new. Since then, I have had several relatively minor issues with it, including common ones with the trackpad malfunctioning (it needed a new battery). Since last night, however, it's ability to connect to the Interwebs has suddenly vanished. It's not like the cause of my problem is a huge mystery; there was another problem involving the apparent 'simulated' holding down of the power button, making it impossible to turn on without force shutting down after a few seconds. This seemed to resolve itself eventually, after I sat up too quickly and it narrowly avoided being badly smashed on my floor when it tumbled off of the futon. Ouch. However, there was a minor bump before I was able to catch it. I worried that it would be broken, but it actually managed to somehow resolve my previous issue with random shutdowns when it turned on. After this, though, I was stymied by it's inability to connect to the Internet at all. I tried WiFi, Ethernet, circumventing the router with another Ethernet cable, and many other possible fixes. No luck. I'm currently typing this on a seperate computer, which has got internet connectivity with wireless on the same network. With the wireless connection, which was working before the power button incident, I am able to see the network and connect, but then I can't actually resolve my connection. In the native internet support program, I am reportedly able to connect to the network and ISP, but not the internet or test server. I have contacted my ISP, and they vaguely insinuated after half an hour on hold that it should be working just fine. Very oddly and suspiciously, whenever I try to open the normal network control panel in System Preferences, the pane blinks briefly and stops responding, to the point that I left it loading and went to bed. This morning, it was still attempting to load that preference pane, and I'm really pretty confused. What is going on? In case it helps, the corner that hit the floor was the upper right hand one, I have to think that it may be a hardware issue, since I've spent quite a bit of time on software fixes. This is my first question to the community so far, so if I've misplaced it or doen something wrong, I apologize.

Thank you in advance!