Okay, I finally fixed the problem!
After trying to plug in the old WBR to use as a temporary router, the same thing happened with that, even though I'm almost sure it worked before. Then I noticed 15% CPU activity, a little odd for complete idle, so I opened up task manager and sure enough there was some program with a name that seemed a bunch of random letters that was taking up about 10% of CPU. Closed that, and voila! Internet worked. So looks like I have a virus, and the virus program I used before apparently sucks! Got a new one now and running a scan, already found some things. Gotta be more careful!