Man, a CZ-75B is a HEAVY all-steel pistol. I can not recommend it for most women.
Get a Beretta 92FS/M9/M9A1/92a1 or a
Springfield Armory XD-9. The Beretta, though, may be too large and heavy a handgun for your wife-the grip may also be too wide. The XD-9 is a superb hangun. Though it doesn't have a manual safety per se, it does have a trigger safety and a grip safety. It's a really accurate handgun and handles recoil well. Have her handle one at a LGS. It is not light, per se, but manageable, with a price that won't break most pocketbooks. It 'points' very well.
And right now you can get three (3) extra magazines for free after you purchase it (or any SA pistol, for that matter), along with a magazine pouch, all contained in a hard plastic black carrying case with the SA logo on it. Check the SA website for this incredible promotion! So far, they are shipping really fast- I can attest to the foregoing.
I'd say S&W Shield. I favor it over most 9mm handguns and it is relatively light. The problem lies with the slide retraction being a bit much for most women to handle- e.g. locking back the slide is a PITA for most females (and some men) due to a tight, heavy, dual-captured recoil spring, even with an empty mag inserted. However, it's a really fun, accurate and reliable shooter, seems to have less recoil and muzzle flip than the Beretta (that was a surprise) but I can not recommend it for most women. That being said, it is fast becoming my favorite shooting 9mm handgun in 25 years of shooting experience.
However, I'd also seriously consider getting a
S&W SD9 VE. That gun is supposed to be a really great
bargain. I used to own a Sigma but this gun is reportedly a later, much-improved iteration, and the ergonomics, weight, and reliability may be just what you both might enjoy! I don't believe that it has a manual safety but the weight of the trigger pull and the trigger safety should be enough. Check it out! Check out the hickok45 video:
https://www.youtube.com/watch?v=1cleMs8xmqc
Do let us know what you end up purchasing- be sure to see how each gun feels in your hands! If that doesn't work for you- despite the other features that may be appealing- you may want to forego purchase of such a handgun.