Education > *
That, and rather than making new laws that only affect people that actually give a shit, work on enforcing what's already there.
Third, hold people responsible. This goes along with number two, but also means that you are responsible for what happens with your gun. If you have kids running around the house and keep a loaded gun sitting out, it is your fault for it being accessable, and it's also your fault for not teaching the kid to leave it be. At 9 years old, a child has been taught and can comprehend was is dangerous and what is not. Also by that age, a child could have gone target shooting with dad, and know that the guns are only to be touched when dad hands it to them. If you don't teach your kids any kind of safety, they find a gun and start playing with it, and end up killing little billy from down the street, guess what? The parent is responsible. Their actions (or lack of actions) caused that to happen just as much as little johnny pulling the trigger.
Personally, I keep loaded guns in the house. I've lived there since february, and not once has their been a kid in my house. There's no way for my dog to either get to them, or manage to chamber a round and pull the trigger, so I think I'm pretty safe from them randomly going off and killing granny next door.