I'm not a shooter and have no interest in shooting, but want a gun for home protection. What should I get? The use of any firearm for self-protection requires at least a minimal amount of training. You must be at least able to safely handle the weapon. You must be able to operate it without thinking. In other words, it's essential that you be able to get it into action without consciously having to think about it. You need to understand how to maintain the firearm, store it where it's accessible yet not available to unauthorized persons as well as how to load and unload it safely.
You must also have already made the determination to the best of ability that you are willing to use the gun against another human being if what they're doing threatens you or another person in your home with serious bodily injury or death.
If you are not willing to expend at least sufficient time and energy to these precepts, you are probably better off without a firearm.
But, what if you are?
As you are not interested in the shooting sports or shooting, I suggest strongly that you use a conventional double-action revolver chambered in either .357 Magnum or .38 Special, but load it with .38 Special +P ammunition. I would take a long hard look at clean, used S&W Model 10's, 13's, and 65's, in either 3 or 4" barrels. A snub is more difficult to shoot accurately, particularly at speed and require more practice to reach the same level of accuracy as its 4" counterpart. With the longer barrels you also get longer ejector rods, which make reloading much easier under stress. They fully eject fired cases unlike the snubs. Ruger offers very usable revolvers in their GP100 line. There's nothing wrong with a Ruger Security Six if you can find them.
There is much debate over the "best" .38 Special load, but I still favor the lead SWCHP +P in 158-gr. as loaded by Winchester, Remington, or Federal. I do not subscribe to the low-velocity 148-gr. full wadcutter in the .38 Special.
If you are determined to use a semiautomatic, probably the simplest "point and pull" pistol is the Glock. I would not get their compact Model 26, but suggest either the 17 or 19, whichever feels best to you. The cocked-and-locked Browning Hi Power remains a superb 9mm, but is single-action and requires remembering more than the Glock to fire it. Make utterly sure that you keep your finger off the trigger of whatever you wind up with until ready to use it.
As you specified "home defense", there is no need to worry about the most compact version of any handgun. While you don't need an 8" barrel, neither do you want to be talked into a small revolver or automatic. Buy something in the "middle area" akin to the service-size handgun.
You may not really want to even use a handgun. There remains much to be said for a Remington pump 870 shotgun and versions with the quick-to-handle 18" barrel can be had quite reasonably. 12 gauge is most common, but they can be had in the lesser recoiling 20 gauge. Some recommend the use of birdshot for over penetration concerns; I use buckshot. It seldom penetrates an adult male torso. If recoil's a problem, and the buckshot will recoil more than the low-brass birdshot, look into the various "tactical" loads available in the buck. These will probably only be available in the 12 gauge.
If you still opt for the handgun and go with a revolver, I also suggest buying and learning to use HKS speed loaders. I'd buy at least three. If you purchase the auto, get at least 3 extra magazines and don't buy aftermarket; go with the gun maker's magazines. There are plenty of good aftermarket magazines but if not interested in shooting, there's chance someone would sell you something not reliable.
The main thing is to be willing to use deadly force if no reasonable alternative exists and to be able to get the hits. That's more important than caliber, load, or weapon type.