“A Remington 870 12-gauge, loaded with OO or OOO buckshot, is the weapon of choice for home defense.”
I agree with the 12 ga, but it should be loaded with #2 or #4 shot.
OO buck is for shooting something 50 yards away, not in your house.
I load my 12-gauge with successive rounds (last in, first out): No.4, No.4, 00, 00, 000, 000, slug.
If 2 rounds of number 4 shot fail to do the job ... it’s gonna get real messy real fast.