We have been looking at various guns but are not sure what would be best for her. Personally I think a shotgun would be best, but the ones I have tend to be a bit much for her length, and recoil wise. She is legally blind but she does have some sight and can see and read with her right eye with glasses, although she has trouble with small detail.
That describes me to a T. I'm blind in my right eye. I have sufficient vision left to read with my left eye, probably more than she does, but I quit driving four years ago.
My husband and I have a Mossberg 500 that serves as our main home defense weapon. We equipped it with a Knox SpecOps adjustable recoil-absorbing stock because I was getting bruises when I shot it at the range and found the long stock difficult to manage. (My arms are a bit shorter than average for somebody who is 5'7".) I don't enjoy shooting it; I have limited tolerance for noise and the thing is *LOUD*. But I can shoot it reasonably well out to about 15 yards, and the limitation is my vision, not my ability to control the gun.
I have tried her with my 12 ga shotgun and my .357 Ruger and they are a bit much for her to handle well. I need something small, short, light weight, light recoil, but able to just be point shot since careful aiming is out. She has said she wants something for protection when I am not around, and getting older, if I kick the bucket she needs some sort of protection when I am gone.
My carry gun is a S&W Model 60-10, a three-inch "stretch snubbie" revolver that shoots .357 and .38 gauge ammunition. I love it, but apparently it's a bit much for a lot of women (and quite a few men) to handle. Point being, people are different, and what works for one won't always work for others. I also enjoy shooting my husband's 1911. Automatics with double-stack magazines don't fit my hand well; I have trouble shooting my husband's Springfield XD-M 9mm. If she has small hands, that might be a concern for her as well.
I can shoot the baby/concealable semiautomatics -- such as the Ruger LCP, the Rohrbach R9, any of the Kahr line -- but I don't enjoy it at all. They're *painful* to handle, IMHO. Most people enjoy shooting larger guns more: the weight reduces recoil considerably.
If you have any ranges in your area that have guns for rent to be shot at the range, or if you have some friends who have guns and would be willing to help with a research project, why not take her shooting to the range? Have a bunch of possible carry guns of all types there, and let her try them all. Then she can tell you which one feels best.