The founding fathers knew English pretty well. If that had been their intent, the Second would have read:
"A well regulated Militia, being necessary to the security of a free State, the right of the [members of said Militia] to keep and bear Arms, shall not be infringed"
Since it does NOT say that, and says that Citizens have the right to keep and bear arms, that is what they meant.
To address some of the other ideas you included - several countries require their armed forces, and equivalent to National Guard, to indeed keep their weapons at their homes.
And at the time the Amendment was written, private citizens owned cannons, and even entire small warships. There was no talk of limiting it to small arms (muskets) - because the idea of that seemed ludicrous at the time.
Please do some research - I am disappointed at the lack of perspective of someone with such a low UID. Sad!