Find yourself a range near you that rents all different types of handguns, and go to town. Before I bought mine, I spent hours and hours in my local rental range just trying all the different handguns, all different calibers, etc. See how they feel to hold, how they shoot, how your natural point of aim is, how your hand feels after shooting it, how easy it is to load/reload/rack-tap, etc, etc, etc. The ONLY way to make a decision on a first gun is to go try them.
A mistake many guys make, me being one of them, is to purchase a handgun for their wives without their wife making the choice. She should be right there with you, making the same decision you're making - Which one is right for me? Have her shoot all the guns, load and reload everything, etc. Have her do EVERYTHING you're doing. Don't make the mistake of just handing her a loaded gun to shoot, when you don't know if she even has the strength to rack the slide, or if her fingers reach the mag release. Make sure she does it all, then she can make a decision from there. One that works for you, she may shoot down immediately because she can even load it.
Also, don't let the salesmen sell you something, make your own decisions. Salesman are especially bad with women, most of them have set in their minds what a woman should shoot, and try to push you towards that. No need to be rude with them, but do what I listed above and pay more attention to what your wife wants, not what some gun guy wants. If she doesn't get one she is super comfortable with, she won't carry it, and a gun in the safe at home won't save your life on the street.
