For a house gun, I would not go less than a 3" barrel on a revolver (prefer 4" or 5" barrel), and I would also want to have a steel frame and steel cylinder. IMO, the Ruger SP101 in .357 mag with the 3" barrel is a very good revolver if she has small hands.
For a handgun I suggest she starts out with a handgun in .22 Long Rifle. This will afford her to practice much more at a much lower cost. I also suggest she takes the NRA Basic Pistol Course.
If she is looking for a house gun, it is hard to beat a pump action shotgun.