what is a good home gun for a woman
I'd have to agree with Paladin on the Mossy .410 pump gun, but I'd recommend stoking it with #4 shot if it will pattern it well.
For a handgun, Ruger's Security-Six or GP-100 series would be good candidates. The 6" variants would be preferable if she's not going to carry them as the longer barrel will help eat up some of the recoil. While I have never shot any through either of mine, they should both handle .38 Specials well. With full power loads (fun, he he), the GP is more pleasant to shoot, IMHO (mine is 6" full lug) than the Security-Six.
The truth of the matter, though, is that while revolvers are easy to use, some women just don't like them. They are loud (muzzle blast and blast from barrel/cylinder gap), DA trigger pull is often heavy, and capacity is limited. Automatics have better capacity, aren't as loud (usually, but .357 Sig is a good exception here), and can be fired a little faster by the average person if necessary. What you need to do is take your wife out and let her shoot a little of everything. Borrow guns from friends if you have to, rent them from the range if possible, and let her decide what she likes. Remember, she has to be comfortable with it because she is the one that is going to have to use it if/when the time comes. If it is not something she is comfortable with, she will not pick it up, or if she does, she will be less likely to use it if it is needed.
Let her pick out her handgun, find a good pump or semi-auto shotgun that she can handle well (youth model if she is petite), then get her to practice with both until she is comfortable with either. Then get her in the state of mind that the shotgun is the preferred weapon and that the handgun is only if nothing else is immediately on hand. Adding some sort of a rifle or carbine (M1 Carbine, Ruger Mini-14, or Ruger PC4/9) to the mix may help. If she decides on a 9mm or .40 S&W Ruger, a PC9 or PC4 would be ideal because they use the same magazines as the Ruger pistols.