small and easy to rack usually do not go together. look for something with the biggest slide she can find. the gun doesn't have to be big, but if the slide is tall and wide, she will be able to get a better grip. my wife is tiny, and she can't rack my cz's, but she can handle my p226. i recommend a da/sa pistol, since the slide will be easier to rack after first pulling back the hammer.
Favorite range gun for the money - CZ 75B or STI Spartan V 9mm
Go-to carry setup - Walther PPS or PPQ in FIST kydex holster 1AK
Favorite semi-auto design - HK P7
"A Sig is like a lightsaber - not as clumsy or random as a Glock."