I learned my lesson at one of Terri ****** Introductory Gun Courses for women who had NEVER shot a gun before serving as a range officer. I brought a couple of 22's. a .380, a 9mm, and figured that would be good enough, and I turned out to be COMPLETELY wrong. Things started out calmy enough with the ladies shooting the 22's and getting familiar with handguns, and then the .380's came out, and then the 9mm's, and they a couple of S&W 40's came out, and an hour later some of the ladies were shooting 45 caliber semi-automatic pistols, and having literally a BLAST doing it. It was literally like watching kids in a candy store. About this time my preconceptions about women not being able to shoot large caliber handguns straight out of the chute were pretty much destroyed, so I decided to go with the flow and asked a few of the ladies if they wanted to try something with a little more punch than a 45. There were about 4 or 5 that did, so i went back to my truck and got out the guns I like to shoot, and for the record, I have the reputation of liking to shoot the biggest and most heavily recoiling guns on the planet. The fiest gun I hauled out was a 10mm, which has 50% more punch than a 45 Automatic, and 4 of the women LOVED shooting this thing, and turned out to be recoil junkies just like me. Then they asked for more, and that day all I had left was my carry gun, which is a very rare piece in 50 caliber. So I hauled that out of my waistband, and the ladies had a ball with that one too, and I went home that night temporarily defenseless because they had used up every round of ammo I had. So, women who have NEVER shot a handgun before can traverse the entire range of calibers starting with .22's and winding up with a 50 caliber (largest allowable by law) IN A SINGLE DAY. Since then I have brought along my Smith & Wesson 500, which is literally the most powerful handgun on the planet right now, and I have had several women in each class who shot it and actually got quite a thrill out of doing it. There was one young lady who was about the age of my oldest daughter (mid 20's), and probably 5'6" tall and 125 pounds at most. She loved shooting the Smith, and went through two full cylinders of ammo (10 shots), and she was blowing the snot of the bullseye while she was doing it. And let's be quite clear about this: This is a handgun that a LOT of men either don't want to or are scared to try to shoot. At the last class I had about 4 women shooting this monster, and I gave each one of them an empty case to take back to their significant other, so they could say: Oh honey, look what I shot today!!
with the express intention of shocking the hell (and perhaps slightly intimidating) the man of the house. 
One other anecdote from one of Ttousi's classes, who had a woman who looked to me to be a complete rookie and was having a VERY hard time shooting a Ruger semi-automatic 9mm. It was clear she just wasn't able to handle that gun at all, and I put it down to inexperience. Stupid me!! After she ditched the Ruger, she hauled out her husband's 4" long barrel nickled 44 MAGNUM revolver, (the Dirty Harry gun...) and proceeded to blow the middle of the target to bits. In this case, she just wasn't used to a semi-automatic, and it made her feel very uncomfortable to shoot it, despite the fact that its recoil was small compared to the 44 mag she was shooting.
So, I've seen it with my own eyes several times, and some women are capable of shooting ANY handgun a man can. There is NO way of knowing before hand what YOU are capable of shooting, and the only way to find out is to try. Along those lines, the best thing is probably go up to Bill's North and get in touch with instructor Theresa ******, and try renting several guns to see what you can shoot and what you like shooting. Once again, DO NOT LISTEN to husbands, boyfriends, or any other male "experts", because you simply won't know what you'er comfortable with until you try it.
As far as to WHY you want to find out what your "caliber limit" is, the answer is very simple: If you are going to carry a handgun for self defense, you want to carry the largest/most powerful caliber that you are comfortable with as far as carrying AND shooting, and most importantly, shooting ACCURATELY. Along those lines, I actually have a REVERSE phobia about small, easily concealable handguns, and I simply WON'T shoot any handgun where I cannot wrap all of my fingers around the grip, and due to the size of my hands that disqualifies a lot of small guns. I just cannot get used to the idea of shooting a handgun while my pinky finger is waving around in the breeze with nothing to hang onto, so I am sure I would be a lousy shot with a small gun, despite my experience and tolerance for any level of recoil. You simply cannot shoot accurately unless you are comfortable with the gun and its recoil.
As one final note on learning more about handguns, various cartridges, and carrying a gun, the best instructional book currently on the market is written by Firearms instructor Mike Martin who lives right here in the TC Metro, and is copiously illustrated with lots of pictures, so you can SEE exactly what the text is talking about. This book is sold at both Bill's shops (Circle Pines - North, and Robbinsdale - South.) You can read posts on this section of the board until you are blue in the face and thoroughly confused, but there is no other document in a stand alone format that will teach you more than Mike's book.
http://www.amazon.com/Minnesota-Permit-Carry-Firearm-Fundamentals/dp/1606438093
I encountered one young lady, probably mid-twenties, who took a particular liking to my Springfield M1A. She would have shot up all my ammo if I would have let her (she even tried offhand too). Last year, I watched one lady fire one of the black powder rifles. She was literally hopping up and down from excitement afterwords. When my wife was taking it, she came and handed me a piece of paper. I asked her what is was, and she said that she had written down her favorites... "Glock 17" and "AR-15"
