I believe the best all-around home defense weapon would be a short-barrelled pump shotgun. Put birdshot for the first couple rounds and buckshot or slugs for the remainder. Pistols like the .40 or .45 will easily penetrate interior walls and could endanger other family members. Bird shot will make a mess of someone at close range but won't go through an interior wall with enough energy to endanger others. The buckshot or slugs would come into play if the bad guy is wearing a vest or thick jacket. A pump shotgun has an unmistakable sound when you chamber a round. That sound alone is often enough to make someone leave in a hurry, perhaps to change his pants. I don't currently own any firearms but if I felt the need for one, a shotgun would be my first choice. For me, a pistol would be useful for having fun with on a firing range.

As for airline pilots, the cockpit is the final line of defense for retaining control of the plane. The cockpit doors have been beefed up somewhat so the crew would have time to arm themselves and point it at the door. There's more than enough room to do that. Frangible bullets can make a mess of someone without punching a hole in the fuselage or a window. A high percentage of airline pilots have years of military service so they've been trained in handguns. By training and temperment, airline pilots keep their cool in tense situations.