My wife is similar in size. We got her an 1100 in 12 gauge. No recoil to speak of. I really feel a 20 is a handicap for a beginning shooter. The only problem with the 1100 is that it is pretty heavy for her. She is doing some weight lifting (really) and that is helping a lot with the upper arm strength. And she REALLY enjoys trap. We are fortunate that there are quite a few women shooting here in VT.