For those of us who will be cremated...
Probably plan on giving them away as the first choice. Becasue even though the temperature will not be hot enough, as a general rule, smelting is not good for barrels :D
Depends on the state...
Water laws are complicated. Some waterways are public below "the oridinary high water mark", some are to the middle of the waterway, some depend on whether or not it's "navigatable", some are yes and some are no, all the time. Usually, however, it is the same within...
Take an air gun with you
They are quiet and fun to shoot on the water -- There are always objects floating around. All you have to worry about is the backstop :)
20's are nice and
Make for good home protection too. But I would suggest that you keep it tight to your shoulder and use "target" rated shotgun ammo :)