
Taking a tangent to Seamus's advice about instruction, Vicki Farnam and Diane Nicholls wrote a two books on women and shooting, if instead of getting another instructor you go the DIY route. You can find them at http://www.dtipubs.com/" onclick="window.open(this.href);return false; One is Teaching Women to Shoot: A Law Enforcement Instructor's Guide, meant for instructors, the other is Women Learning To Shoot: A Guide for Law Enforcement Officers, meant for female students. Making sure she has a good grasp of both the gun and the ideas can go a long way towards making the gun easier to handle. Altho these books were motivated by the author's experiences in training law enforcement officers, they are equally applicable to any one who shoots, not just cops. The focus is on shooting, not policing. The best would be read these two books, and then go to one of John Farnam's basic Defensive Handgun courses -- Vicki (his wife) teaches those courses, male and female students both, and she is good at it. There is one coming up in October in Victoria, Texas.
As for the gun -- bigger gun in same caliber will have less recoil. Simple physics. If it is really the recoil that bothers her (versus, say, maybe the way she is holding it amplifies the felt recoil), then the more metal and the smaller the caliber, the easier it will be.
My wife has had trouble with the slides on the Keltec and the Kahr P-9. Smaller guns have stiffer springs. She does better with the Glock 17, but it is still a chore, and the Glock is pretty big to haul around for her. She ultimately decided she liked shooting my snubbies best overall. Simple to operate, easier to pull the DA trigger than rack a slide, etc. I got her an Airweight bodyguard with a CT laser (I am not big on lasers, but she likes it) as a gift, and that is what she will carry and shoot. Good for most short range encounters, harder for someone to grab with that short little barrel, and she can shoot right thru her purse with it (I hate purse carry, but I am not her). Loaded with standard Corbon DPX.