Home defense firearms for beginners? 12 ga. shotgun and .357 mag revolver.
Yep...Mossberg 500, eight shot mag tube, running alternating double-ought (00) and deer slugs, with a deer slug out first. Even better if outfitted with a Pachmyr Vindicator kit. Might want to scale down to #2 shot and skip the deer slugs if you never take it outside.
Also, Chas Daly 1911A1 .45 semi-auto. Fitted with Chip McCormick 8-shot mags, it’s an excellent house gun. I like good ol’ 180 grain ball ammo for indoor use.
Third choice is any good .357 magnum revolver. You can run .38 ammo if you wish, but the magnum loads are faster, flatter, and offer more knock down in my experience. I like Dan Wesson, S&W, Ruger, and Colt. My favorite load is a 125 grain jacketed flat point on Unique powder and a magnum primer from CCI.
The Remington 870 is my favorite shotgun:
And I love .357 revolvers: