A nice big decent weight revolver, probably in 38 special. Have her pick up several and figure out what size/grips fit her hands. If a J-Frame size fits her, go steel not light weight alloy. The weight is important to soak up the recoil, so she doesn't hurt/break her wrists. It's not like she'll need to carry it for hours shooting in competitions. Just a bit of practice every couple months.
Then have a set of big dot sights put on: http://www.midwayusa.com/product/676...ar-steel-matte
Some light loaded ammo works well: http://www.hornady.com/store/38-Spec...-Defense-lite/