What I mean is, as much as I like big guns (AK 47 FTMFW!!), IMHO I'd pick a samurai sword over any gun for house defense, any time of the day. I mean, it's not like burglars with UZIs are breaking into houses now, and the only way to defend yourself is with an AK-47 and planting some C-4 all around your house...
I think you would be at a disadvantage if you were using a sword in a confined area like a small house. A handgun would be far less unwieldy. The intimidation factor is quite high on swords though - sometimes moreso than guns, which is hopefully all you need to resolve most issues.
If I were a kid, I'd be awfully tempted to swing around a kick-ass looking sword so I wouldn't consider simply mounting them in a high place as "kid safe". Hell, I'd be tempted to now if I didn't know better than to play with something that I have no training with.Besides, in case somebody _Does_ break into your house, you may not have enough time to get your gun (y'know, keeping them away from children and stuff), instead you can just keep your samurai sword on a shelf or rack in your living room (far far away from a child's reach)...