For emergency use I'd recommend a Coleman 2 burner camp stove. Even when all my car camping gear is packed deep into storage, the stove stays in my bedroom closet with a few cylinders just in case. Same with the propane lantern.

I'm not aware of any 'multifuel' propane stoves on the market.

Coleman also makes some good propane heaters but the Mr. Heater models are also very good. Whatever you get, get something with safeties that turn everything off if the unit gets bumped or knocked over.