As mentioned before, the best for you is one that fits your hand. Put the grip firmly into the web between your thumb and fore finger. Line up the barrel with the bones in your arm. Now, can you operate the trigger? Test fire something in that caliber. Is the recoil uncomfortable for you?
How familiar are you with handguns? The style that's easiest to determine whether it's loaded or not is still a double action revolver. They are a good place to start, and my wife would argue a good place to stay.
And then there's budget. It does little good to buy a firearm that is so expensive or expensive to shoot you can't afford practice ammunition.