For a plinker, check out Ruger’s Single-Six if you want a revolver, or the Mark III for an auto. Both are chambered for .22 Long Rifle.
For protection, Ruger’s Double-Action revolvers are a good choice, too. The GP100 .357 would be good for a larger adult, and the SP101 in .327 (yes, that’s a two, not a five) might be an option for you.
DA revolvers are a good choice for anyone who doesn’t want to spend a lot of time getting to know their gun. They are simple to operate and generally don’t malfunction the same way a semi-auto can. There is also the issue with automatics where the slide return spring is too strong, and some people can’t rack the slide. I’ve seen this happen, and it is potentially very dangerous.
I love my single six, but would hate to try and shoot effectively without using my thumbs.