Look at what is available and make your choice. Then Practice, Practice, Practice.
Actually that is the best choice in the home, assuming you don't want something to carry along too. I keep mine loaded with #7 1/2 birdshot though, so I don't kill the neighbors. I figure an ounce of birdshot to the face at point-blank range should be very discouraging.
This is good advice that I've followed for more than 20 years.
Go shooting with a friend that has a handgun, any caliber will do. Have a safe backstop behind your target, take a card table & set it up about 15 ft in front of your target. Carefully lay the loaded handgun on the table, now get back 100 yards. Sprint to the table running hard as you can. Immediately pick up the handgun and shoot the target.
This kinda sorta duplicates the adrenlin rush you get when in a dangerous situation, complete with heavy rapid breathing. It's harder than you might think.
I remember in the late '80s in Dallas, I think, when a perp pointed a shotgun at a group of 4 or 5 cops, ranging from 15 to 20 feet away, that had been chasing him (car chase). They all already had their guns drawn when he did this and they commenced to unload on him. More than 40 shots fired. Seems like they hit him 2 or 3 times and he dropped the shotgun without firing. They then had to call an ambulance to take him to ER.
It can be difficult to hit with a handgun when under pressure.
I say choose the shotgun and use bird shot. It is very effective at home defense ranges(10-30 ft) and makes a hamburger hole an inch or two in diameter that a doctor cannot put back together, but is less likely to penetrate your walls and endanger your kids than buckshot.