Shotguns, generally, are not the best option for home defense. Many states have regulations on minimum barrel lengths, making them too long to be safe or easily used indoors. Check your state's laws first before deciding on purchasing a shotgun for home defense. Remember, usually the length specified is barrel length, not firearm length, so it would likely be a 3ft piece of metal you are swinging around corners. I would recommend finding a local range that offers the ability to rent firearms to use on their course (there's one near my house that allows you to rent any style for $8. Try out several hand guns and see what you like. Generally, you've got two or three options when it comes to caliburs: 9mm, .40 and .45. .45, obviously, is going to give you the most stopping power, but that is gained through sacrificing magazine capacity and reacquisition time (time between firing, managing recoil, and retraining sights). 9mm is a great round for starters, as it offers decent stopping power without tremendous recoil. .40 is obviously in the middle, but I wouldn't necessarily say it's the best of both worlds. Your primary shopping points are going to be what is legal to use in your area (your gun shop and personal research should help with this), your budget, and what feels "right" in your hands. The later is the most important option, as a firearm should be something that is comfortable and easily controlled for safest and most appropriate use. I can't recommend any .40 or .45 handguns, but check out the XD series firearms from Springfield armory. My roommate owns an XDm, and I've always been pretty fond of it.