My suggestion would be:
Colt Mustang .380.
A lot of folks might recommend other small 9mm's or .380's that are Double Action Only. The problem with double action only guns and really small hands is that they tend to have long heavy triggers. If you have small hands and short fingers, you will be struggling with the trigger. The Colt Mustang (Sig also makes a variation of the same gun) is a true single action only, which translates to a short, light trigger pull. The J-frame S&W will have a heavy trigger pull as well, as do most revolvers. The right SAO semi-auto is actually better for really small hands than a revolver. If the Colt Mustang is too small, then try a Walther .380.