I wouldn't be quite so absolute about the handgun vs shotgun. Hitting the target is everything. If someone isn't going to put time into practice as you said, any shotgun is better than a handgun IMHO.
I learned shooting a firearm at 10 years old with a 12 ga. Then I moved to rifles. Both were easy to learn and use. To this day I can hip shoot better with a long gun than I can in my best modified Weaver stance with a handgun. Ok, I've got 30 years more experience with long guns. But still...
A revolver is the only choice for such people.
BTW, this is one of my bedside weapons. It started as a standard Rem 870 Express HD. I replaced the stock w/a Knoxx so as to increase it's portability/maneuverability. Then I decided to try to increase its versatility by replacing the 18 inch HD barrel with a 20 inch turkey barrel. I'm going to use it for turkey, varmint and HD.
It's still a massive gun, regardless. It's loaded with 00 buck. Someone might suggest that with that choke there's not going to be any spread. To that I would say they should actually pattern a shotgun. At across-the-room distances, there's not going to be much spread anyway. That holds true for your argument re revolver vs shotgun. If you don't believe it, pattern your open choke 18 inch barelled shotgun at say, 10 or 12 feet.
I also have a Glock 19 with tac light in my bedstand. Also in my bedstand is my everyday carry piece, a Sig 239 DAK SAS.
If I have to clear the house, I use the Glock that is alternatively loaded with hollow points and solid points. Solid points for penetration (in case bad guy has lots of clothes on) and hollow point for expansion.