No firearms at all
Non-automatic rifles and shotguns
fully automatic weapons
military-grade explosives (hand grenades, mines, etc.)
Any man-portable weapon in use by the military
Military vehicles and vehicle-mounted weapons (tanks, jets, etc.)
No restrictions on civilian weapon ownership at all (up to and including nuclear)
Other (please explain)
Of course, the word "arms" when the amendment was written consisted of muskets and cannon. The Second Amendment needs to be re written, but can you imagine a rational and reasoned debate on the subject?
OMG! The commie liberals are going to take our guns away! I told you so, told you! They'll get mine out of my cold dead hands...
and etc. and so on ad nauseum.
Can't we just turn Congress off and then turn it back on again?
A well regulated militia means well trained. Then it protected, from government interference, the right to keep and bear the kinds of arms an individual soldier, an infantryman, would use. As technology changes the Second Amendment's interpretation should move with it. The typical infantryman today carries a semi-automatic rifle with the ability to select automatic fire.
I would add all lesser included weapons, such as shotguns and pistols.