Will, if you have a Gander Mtn. anywhere near you, they have three versions of an 18.5" VR /RemChoke barreled 20G Youth Jr. 870 Express.
One has pink laminated furniture and "Shoot like a Girl, If you Can" (lawyer proof

) engraved on the stock.
The second has blue laminated furniture, and "First in the Field" engraved on the stock.
The third option will be a normal (unengraved) laminated wood-stock.
All have the same basic specs:
http://www.remington.com/products/firea ... ess_jr.asp
I think these are the best thing going for "entry level" shotguns for kids, women, and/or anyone who might be recoil sensitive. 20g target loads are expensive, but the Youth Jr. models are based of a full sized 870 action, so practice with the gun shouldn't be painful. Federal's
P256 Loading (20 pellets of #2 Bk @ 1175 FPS) should do just fine for HD.
Buy the gun, add an
XS BigDot, a Vang safety, and you're GTG with a plain-jane defensive 20G for HD.
ETA: I agree with everyone else
in principal about 12G, though. Wider variety of ammo, along with a HUGE selection in low-recoil HD options makes 12Guage super versitile. That said, the little 20's above do have less mass to swing around with enough weight to mitigate most of the bite from a light 20. They also come with a short LOP stock from the factory, which is another big plus in my book.