I'm going to give you three pieces of advice, first get a caliber which has low recoil and cheap ammo available so you can shoot alot. These would be 22LR, 38 Special, and 9mm.

Next, I would suggest a revolver for ease of shooting and ease of being safe. With a revolver, when you pull the trigger, they go bang. When you are not touching the trigger, they do not. Auto's are easy to unload and due to the wrong sequence of actions, have your gun still loaded. Auto's are also relatively dependant on spring pressures for function. So when a spring wears out, it can be an issue figuring out why the gun isn't reliable. This can even happen with a new gun. This timing is much more complex than revolver timing. Anyways, there is just a bit more hassle potential with an auto.

So to answer your request for a reccomendation. . .First, I would reccomend a standard size Springfield XD-9. These are generally reliable out of the box. 9mm is easy to shoot and fairly defensively capable. They also have a good grip shape and angle. Their finger on the trigger for shooting mode and finger off the trigger for safety, is a nice simple to learn action system.

My next and better reccomendation. . .A Smith and Wesson model 10, 64 or 686 revolver with a 4 in barrel. These are great guns because you can shoot 38 spcl rounds which are very unintimidating to shoot. The mid sized revolvers have 100's of different grips available to fit almost any possible shooter. The triggers are good out of the box. Then, with the 686, you have the option of loading up with the 357 magnum round for short range deer or a stronger defense round. In that way, it kind of grows with you. Used model 10 revolvers can be had for under $300 and are generally ready for many more years of shooting! These are ok for CCW, but better suited as a range gun or home defense gun.

The last reccomendation is to get a 22LR. A 22LR revolver is a great way to learn shooting handguns, shoot 1000's of rounds of cheap ammo and generally have a blast. In an auto, the Browning Buckmark is a very good 22LR auto.