I never really did follow up with this saga about my computer and its impending molten death.
After he found the potential trojan (which ended up being nothing, really), J cleaned out the whole computer with some virus software and then compressed air, and we tried to start backing things up before the whole thing went up in flames. I felt like I was racing the clock.
The next day, after a third sudden shutdown during an episode of Aqua Teen Hunger Force, I had had enough. I was ready to throw the thing out the window. Instead, I sighed, and unplugged it. I flipped it over, and went at it with the air can again. This time, I noticed a little bit of hair in the fan, so I picked up a pair of tweezers. Instead of a little bit of hair, I ended up pulling out a dust ball the size of a small mouse. I don't even know how that much dust managed to get into my fan, but there it was.
My computer was instantly quiet. More efficient, perhaps, but more importantly - quiet. And no longer shutting down suddenly for no good reason.
Since this resolution, my computer has gotten progressively louder again, and is almost as loud as it was at the height of it's near-death. It seems the honeymoon period was over before we even got started. Stupid laptop.
So the long and short of this whole unfortunate business?
I'm getting an iMac.