Okay, the lowest recoiling semiauto handgun you are going to find is one chambered in 22LR. Which specific model, well, as there are dozens of them, ask that question later. The 22LR has almost no recoil AND the ammunition is very inexpensive. This means you can learn the fundamentals of shooting well with that gun.
Unfortunately, while the 22LR CAN definitely kill the classic wound of the 22LR is something that causes a person to bleed to death in a few minutes. Unfortunately this means if the person who is shot is your attacker he generally has a minute or two of full functionality before he succumbs to the 22LR's wound. SO he can be shot with a wound that ultimately proves lethal and still finish stabbing his victim to death.
The flip side of this is 9 times out of 10 simply seeing a handgun in the hands of a determined non-victim, even the most hardened criminal will flee.
So, if you are serious about getting a defensive sidearm, you'd want something with a bit more power. Sticking with a 22R for home defense is like a homeowner who recognizes that while unlikely, a house fire IS possible, but rather than buying a fire extinguisher said homeowner simply keeps a glass of water on his beside table to throw on any small fire that may occur.
So now let's talk recoil.
There are two factors in recoil. The more powerful the cartridge, the more the gun will recoil. The heavier the gun, the less it will recoil. So a light weight gun firing a medium power round may well recoil more than a big heavy gun firing a big powerful round. Keep this in mind when you do gunshop. Many new shooters are drawn to small guns thinking subconsciously they will recoil less.
You must also consider 'gun fit'...a gun that is too big for your hand will make the recoil seem worse. Because of this it may be advisable for a person with small hands to try out small guns because sometimes small guns are the best place to find small grips. With semiautos, a lot of the small guns have fat, wide grips which defeats the whole reason for going small. One feature to look for when buying a gun is that it has a 'single stack' magazine, as these guns will be slimmer in the grip. A single stack magazine gun generally holds 6 to 9 rounds not 10-15. Also note that a lot of 'small and fat' guns leave your pinky or maybe two fingers hanging. More grip to hold onto will mean more control and less kick.
For fit, the BEST thing to do is go to a shooting range and dry each gun. However, that isn't always practical. Simply handling the gun may have to suffice.
NOTE: most gun ranges rent a single gun for the entire session, however if you go to a gun store that also has a gun range (or vice versa...a gun range that has a gun store) you may have luck talking to the salesman and arranging a special deal where you buy a box of ammo and try 5-10 guns for a short period for a slightly higher price than normal. Try offering $30 to have access to 5 guns.
Okay, I mentioned power. Probably the most common round out there that pretty much everyone finds controllable is the "9mm" properly called 9x19mm (9mm wide, 19mm long case), 9mm luger, and/or 9mm parabellum. This is because there ARE other types of 9mm.
I am going to suggest some guns to try out. These are all 'single stack' 9mm handguns, and hence will be 'thin' but will be fairly sizable to have decent 'heft' to absorb recoil.
Sig Saur p225 in 9mm (most often encountered 'used' as the surplus SIG P6)
Sig Saur P239 in 9mm - a refinement of the 225
Walther PPS in 9mm (note NOT the walther PPK of james bond fame) a wonderfullly slim gun
Kahr K9 in 9mm...standard size, NOT polymer (you want the hefty steel frame to absorb recoil)
Taurus 'slim' 709 in 9mm
If, in the end, you decide the 9mm is too snappy for your recoil tastes, then stepping down to a 380 ACP it is also called 380 Auto, 9mm Short because it is 9x17mm (which means the case is a little shorter and hence less potent) It also goes by 9mm Kurz...german for short.
Note that right now the market is awash in very compact very lightweight 380 ACP pistols, to the point that they are light enough and small enough they will recoil MORE
There is one 380 acp pistol I can recommend as an absolute GREAT purchase for anyone who is recoil shy: the Beretta 85. It looks very similar to the Beretta 92F 9mm handgun made famous in the movie Lethal Weapon. It is a very well engineered gun, solid to absorb a lot of recoil, yet thin. It has a brother the Beretta 84 which can take a 13 round magazine which means it is wider. Beretta still makes both and they are both very popular in Europe, but many gun stores here in the USA don't stock them. They can of course be special ordered.
If the other 9mms are just to much I have enough confidence in the beretta 85 to advise a person to have it special ordered blindly because they WILL find it controllable and significantly softer.