my 2 cents.
If your recoil sensitive, then skip the NAA. The .22 mag will not kick horably but will roar and throw a considerable muzzle flash out of such a short barreld gun. Muzzle energy/velocity will also be greatly reduced as that round needs a longer barrel to burn that slower powder.
Of the 2 calibers mentioned , I'd note that the 22 mag is going to be ALLOT cheaper to practice/shoot with. The .32 ACp is just too uncomon to find cheap ammo. The .22 mag would be better out of a 4" to 6" barrel if you want efficiency though. FWIW, I'd vote you look for a good 3-4" medium frame revolver in .38 ( or 357). 38 target ammo in a K frame S&W will give about as much felt recoil, noise and flash as a smaller lighter .22mag. It will be cheaper to feed than either round, increadibly reliable and super versitile. Grip options for the S&W are infinite and sutable for any range of hand sizes. lastly, used 38's are EVERYWHERE and often priced well under $250 for a nice one.