Yes you are correct...tombstoning is the process that a capacitor, resistor, or other similar component either raises to one end, or rolls onto one side (although this is very rare....the side roll).
This is usually from them smt pad being larger than the component soldering location. The surface tension of the molten solder will pull harder on one end than the other......resulting in a tombstoned part. This usually happens from more solder than required to attach the component to the board. A smaller pad would require less solder....and the surface (smaller quantity) tension of the molted solder doesn't lift the part.
This is not a total explaination....because a larger foot print usually extends past the component end(most hand solder pads are longer....but not much wider)....this added area is leverage for the molten solder to help raise the component as well.
You should know that when hot air soldering.....turn the air volume down as low as you can get away with. The air flow will provide an addition lifting sorce for the parts. This could result in some very frustrating moments. I have done some rework to my boards.....and have found out the hard way.
I can't say about the footprints.....I was asking to know if there were different ones for reflow or for hand soldering.
I'm batch reflowing....so I've not had any tombstoning while reflowing total boards.
I'm also very careful about placement.....make sure your parts are pushed down into the solder.......don't go crazy....but make sure they are in contact with all their landings. This helps prevent one side lifting. (But this is theoretical....and my opinion)