Arm yourselves for Civil War II. Republicans are, you'd betterIdeally, every adult and teenager in your family will have an AR-15 carbine. It's the first choice for many reasons, not the least of which are availability of ammo, magazines and spare parts. Mild recoil.
Browning Hi-Power, finest handgun in the world. Mid-sized single-action fits all but the smallest hands. Get it in 9mm.
Ruger 10/22 semi-auto in .22 Long Rifle is perfect even for small children. Comes with a 10-rd magazine, but magazines holding 30 (pictured) or even 50 are available.
Youngsters need pistols, too. The Colt Mustang "Government Model," in .380, fits all but the smallest hands.
On a budget? Get a Yugo SKS. Good ones can be had for around $100, and use stripper clips, meaning you don't need magazines. Take that silly grenade launcher off, and go.
The CZ-52 is an excellent sidearm for adult hands. New ones can be had for about $100.