Another problem which started occurring at the same time is that I can only maintain a connection to a wireless network for approximately 1 minute (until a CPU spike, maybe? I'm not completely sure, but now that I think about it, it's possible). Every other computer in my house can connect just fine, and this laptop could too until the other problem started as well.
I'm running 64-bit Vista, and I sincerely hope that it's not a physical problem with the computer, as I'm leaving for a very long time in 3 days. I don't think I've had the computer long enough for the culprit to be spyware or a virus, but just in case, I captured a Hijack This log: