A small 38 revolver would be a safe and easy to function gun for the lady but I feel that a good compact 9mm auto would be a better choice. A compact nine holds more ammo, is faster to reload, and for most new shooters the trigger pull makes it easier to shoot compared to the double action pull on a snub nose revolver. I would suggest taking her to the range with the revolver and and a good compact nine like the Glock 26 or S&W shield and see which gun she shoots best.
Agreed.......unless she's unable to find a semi that she can work the slide on. Good suggestions above about trying out as many models as possible. My wife started out shooting a semi auto, and was amazed at the increased noise and muzzle jump of a snubbie over a semi, and didn't care for them because of it.