Great summary, Bearpaw!

For the OP, propane (being more explosive) requires much heavier canisters than does butane. Propane canisters are far too heavy for backpacking.

The isobutane canisters cannot be refilled, but they can be recycled. Punch a hole or two in the canister (do this outside, obviously, after making sure (with the stove part) that all fuel is gone) and let it sit outside for a day for everything to evaporate. At least my local recycling folks haven't objected yet. Some outdoor stores will recycle your used canisters, too.

The "multi-fuel" stove is pretty much the same as the white gas stove (many of the "white gas" stoves will use kerosene, the common fuel in other parts of the world). IMHO, too heavy except for cold winter use, when canisters wimp out and you need to melt lots of snow for water.