The term "people", in the Second Amendment, means the same as elsewhere in the Constitution and Bill of Rights: "free persons". Arms Restrictions for convicted felons are covered under Amendment XIII.
The function of the first part of the Second Amendment is to clarify what is meant by "arms". The term does not include every object which could conceivably be used as a weapon (otherwise the government would be unable to tax or restrict anything) but rather refers to such objects as may be used effectively as weapons in the context of a well-functioning militia.
The Miller case (last 2A case heard by the Supremes) was about a sawed-off shotgun. Apparently it was a type of weapon used by the military, which tells you that the lower courts agreed that "military use" was the criteria they would live by.
Of course, RPG's are 'military use,' as are FULL-auto rifles, 60cal's, etc.
If you really want to have fun with someone, ask them which 'military' weapons 'the people' are NOT entitled to under the 2A.
I want a BlackHawk.