In this room you have your firearm, ammunition, and a cellphone. (A regular phone works fine until the wires are cut). If you think you have trouble, gather the clan, lock the door (a steel-frame door with a deadbolt works best, but NOT one of those hollow-core pieces of trash that are your usual interior door), call the cops, chamber a round, and wait for help. Teach your wife to respond this way. Drill the kids.
I strongly do not recommend clearing a house on your own - the SWAT guys certainly don't do that. And above all, no warning shots. If you have to pull the trigger the situation is already in extremis and you're only wasting ammunition.
I certainly agree with all that.
Just as having fire extinguishers doesn't make me a firefighter, I don't plan on becoming a SWAT officer just because I have some guns.