I think a person can 'learn to shoot' on a wide variety of handguns if his first purchase is going to be a dual purpose 'to learn..but also to defend' handgun.
I'd suggest getting a reasonable starter gun that will also work for self defense, then augmenting this with a .22handgun.
Alternatively, augment it with a .22 rifle, the basic skills of trigger control, sight alignment, etc, all still apply, and you can generally pick up a very solid used .22 rifle for $100-$150
That being said, there is nothing WRONG with starting out with a .22handgun, or even buying 2 guns at once! Especially if you are going to get a 22 that is very similar to your primary gun.
So what would I recommend for a dual purpose 'Lean to shoot...but also defend' handgun?
a full sized 9mm handgun would be a good choice. Something from Sig, H&K, Walther, Smith and Wesson, Beretta, Colt, FN/Browning, Glock, Springfield XD, Ruger, Taurus, CZ...Humm, I think that is pretty much it for a list of reputable makers. I may be missing a few but close enough. Features to look for. You want a FULL SIZED handgun. Think which will jump more, a firecracker put under an empty pop can, or a firecraker put under a cast iron skillet. Heavy is your friend. Semi-auto handguns come in 4 general sizes, Full sized, Compact (really, this is more 'normal' that truely compact) Sub-compact, and micro. Stick with full sized guns or at best some slightly compact ones, Think Beretta 92, Glock 19 or 17, Ruger p95, etc. Generally these guns are going to be designed to accept a 15 round or higher magazine. You want a gun where you can get ALL your fingers comfortably on the grip, no pinkie hanging off. Also, some of these guns can tend to be a bit wide in the grip, make sure you can get the joint of your trigger finger on the trigger easily, and reach all the controls easily.
The second option I actually recommend even more strongly. Start with a .357 magnum revolver. See, a little known fact by gun novices (doesn't come up in most video games or movies) is that a .357 magnum revolver can ALSO shoot 38 specials, no change needed whatsoever. 38's, being a bit less powerful than 9mm will give you a wonderful starting ammo. You can also load (and shoot) 38 special +P ammo, where +P means it is a bit more powerful, and probably not a good idea to shoot in a 100 year old gun, but gives pretty much the same power as a 9mm. As your skill and confidence improves, you can do a mix of practicing mostly with 38 specials, but also a few 'medium velocity' 357 magnums, and then having those same 357 magnums loaded for self defense. And yes, there are boxes labeled 'medium velocity' or 'low recoil' or 'medium recoil' 357 magnum, and they are head and shoulders above a 9mm in power. Beyond that there are full power 357 magnums, for when you truely know you can handle the recoil.
Plus, a revolver as a few factors going for it. If you choose a 4inch or 6inch barreled gun with adjustable sights, you get a gun that will be very easy for you to learn to shoot on. Plus, revolvers are an inherently STRONG design, that's why you always see the newest biggest baddest calibers being found in revolvers before anything else. Additionally, revolvers tend to have very nice trigger pulls, especially 'single action'...that's where you pull the hammer back with your thumb. Revolvers are also an inherently simple design, I find starting shooters like being able to see all of what is going on, simple to loadn and unload, etc. Finally, while both modern revolvers and modern semi-autos are very reliable guns, and can take a LOT of abuse before failing, revolvers are in my experience, much better at standing up to neglect, such as being left in a dresser drawer under a stack of socks for 10 years. Taurus, Ruger, and Smith & Wesson are the big revolver names to look for.
Finally a bit on termenology you will probably encounter.
Revolver - You probably already know what this means, but what the heck. Revolver is a handgun where a revolving cylinder brings the next cartridge up to be fired as the hammer moves back. If for some reason something fails to work, the revolver can rotate a bit more cylcing another fresh round as the hammer moves back a second time.
Semi-automatic- Sometimes called just auto, or autoloader, the auto takes a small amount of the power of the exploding gunpower and uses it to both eject the empty shell and chamber a new round, and finally, also cocks the hammer. Note, for the first round you must manually work the action to pull a round from the magazine (or clip) and put it in the chamber, lined up with the barrel ready to fire.
A second layer on this is Single Action or Double Action. You can have single action revolvers and double action revolvers, single actin autos and double action autos.
Single action---Does ONE THING, and one thing only, it drops the hammer.
Double action---It does 2 things, it first pulls the hammer back and cocks it, the second thign is it drops the hammer once it has been cocked
For both a single action revolver and a single action auto, you can pull on the trigger all day long and accomplish nothing. First you ahve to get the hammer cocked somehow, normally with your thumb. In the case of a revolver, this will also cause the cylinder to revolve, lining up a cartridge with the barrel ready to fire. For an auto, you need to already have a cartridge lined up with the barrel ready to fire, or you will just be dropping that hammer on air.
For the single action revolver, you pull the trigger, hammer drops, BANG. Now you start over, pulling back the hammer to revolve another fresh round up, then pulling the trigger BAM! etc.
For the single action auto, remember, it has harnessed some of the exploding gunpowder to eject the old shell, chamber a new one AND RECOCK THE HAMMER. So all you ahve to do is pull the trigger to drop the hammer a 2nd time, and BANG again.
Double Action revolver, there is a mechanical tie-in between the trigger and the hammer. This makes the trigger pull longer, as you are also pulling the hammer back at the same time with one finger (you can manually pull it back with your thumb still if you want, makes it easier on your finger, the gun shakes less as you do it, and that means a tiny more accuracy when you DO pull the trigger) As the hammer goes back (from the trigger being pulled) cylinder revolves, a new round is lined up with the barrel, then BANG. YOu can keep on pulling on the trigger and the gun will keep on firing. If the hammer would fall on an old bad cartridge, just pull the trigger again the cylinder will revolve more and a fresh round will line up. Unless you are cocking the hammer with your thumb, all the trigger pulls will be long.
For a double action auto, again the trigger is manually linked to the hammer. Pulling the trigger will also cock the hammer, but as with the semi-auto, you first must have a cartridge lined up with the barrel ready to fire...however, no need to cock the hammer with your thumb, just pull the trigger. Like the revolver, this trigger pull is going to be longer and heavier, as you are pulling against a cocking spring with jsut your finger, not your strong thumb. However, you only have this long hard pull ONCE, as after you shoot, the gun recocks itself, so on the 2nd, 3rd, 4th, etc shot, the hammer is allready back. This means you will experience two very different trigger feels when shooting a double action auto.
Because the experience of pulling the trigger of a double action auto is much different at the beginning people actually disabled part of the autoloader actions so that the hammer didn't automatically recock. They did this especially for police, because they wanted every shot to require a long deliberate trigger pull, not just the first shot. This subclass of Double Action Automatics are called Double Action ONLY. They also normally have the hammer bob cut off so you cannot grab it with your thumb, so no matter what, all shots are going to be long and deliberate.
Some people have also done the same with revolvers, cut the bob off the hammer of a double action revolver, so you cannot cock it with your thumb, but really the reason they do this is because some people like to stick a small revolver right in their pants pocket, and that hammer would snag when they tried to pull it out. The idea was 'hey I am using this thing for self defense, not target shooting! I'd rather have an easy time pulling it out of my pocket, than the option to cock the hammer like some target shooter, I am not going to take the time to carefully thumbcock the hammer, if I need my gun for self defense I am just going to be yanking that trigger back and shooting!'
