When you are in your house and shooting 00 buck you are basically shooting the equivilent of nine 357 magnums in your house or apartment if using a 2-3/4" shell. Not good for anyone on the other side of the wall.
Firing any firearm toward a wall with people on the other side is a bad idea. Changing from 00 buck to #6's doesn't absolve the responsibility of "knowing your target and what lies beyond it".
I use 00 buck, because I expect it'll stop the badguy sooner and more decisively than smaller shot. I do this because I expect if I'm forced to shoot the badguy, I'm not the only one in the situation armed and I want his trigger finger to stop moving ASAP. I know where my family is in the house and which walls not to shoot toward. He doesn't and if he did, probably wouldn't care.
Ergo......buckshot for me.
As always YMMV.....