Why do you have .38Spl and .357 Magnum under one ammo type? I believe there is a real difference. Well maybe not that much with a short barrel, thats right.
Concerning the original question, many agree that there is no reliable one shot stopper handgun caliber, and everything what matters is a shot placement. So maybe it would be better to ask about a gun type.
From my point of view there are actually only two main categories, a pocket gun, and a normal fullsize gun.
For a pocket gun the winner is a snubnose revolver, which means your .38Spl/.357Magnum combination.
For a normal handgun (holster c.carried) I believe the caliber is not that important. You just need something you will carry without problems, and practice with quite often. So you can place that shot where it counts. I'd go for Glock 17/19 for no fancy all bussines everyday carry pistol since it is light and small for it's capacity. You will have more practice for the same money, and practice is what's most important. Note that G21 feels the same as G17 so if you are into .45 a lot, you can always buy a G17 for practice and G21 for carry.
I'd not really consider anything else than .357Magnum, 9x19 (9 Luger) or .45 ACP, because these are the most common calibers, and therefore available and relatively cheaper than the other stuff.
For a pleasure shooting, I prefer my CZ75 in 9 Luger, and since I generally prefer DA/SA system, and have a soft spot for CZ guns, I'm looking forward to see whether the new P07 gun would really become the DA/SA Glock alternative. So far we know that it's surely about as ugly as a Glock.