Telling your small child you have guns for shooting zombies is one way of explaining your firearms to them. He can even get in on the act, buying you zombie themed targets and ammo. But, be warned, if you take him here:
Do not be surprised if he loudly shouts out, "My daddy has a gun for shooting zombies in the head!" in front of every man, woman, and child.
Also, the Planet Terror 2: Electric Boogaloo burger is friggin' awesome.