Anyway, I thought I'd just post a few photos of the long radiator that Katherine and her mom removed one day while I was at work. Turns out they're fairly simple to dismantle and cart away.
Here's the tools required for the job next to the offending radiator:
The first step is to remove the tie rods (my term) that hold the whole thing together. You should be able to unscrew them with a good socket wrench, but it's more manly to use a sawzall.
Then you just use your pry bar and your hammer and your muscles to work each section apart until you can carry them away.
There's a lot of debris that'll probably fall out of your old radiator so you might want to put something down beforehand to catch it. You also obviously want to have drained the water out of your system before breaking the radiator apart (my father and I had already cut out all the old water pipes in the basement and removed the boiler so everything was pretty dry, but there's always the possibility that some water could be left in the bottom of the radiator).
And that's basically it. You'll probably need to do some wall and floor repair, and if you've still got pipes running up through the floor boards you'll need to remove those as well (a good monkey wrench or sawzall will take care of that though). And then haul everything to the recycling center and cash in some of that old scrap iron.
Piece of cake...I guess. Again, it was all done by the time I got home from work.