Andrew, if you have no intention of carrying and want a good home defense weapon get a 12-guage pump action shotgun. If you get a regular (not pistol grip/short barrel) you can use it for home defense, busting clays, hunting birds or even deer. They are very versatile, cost $250-300 and will last a lifetime. Remington and Mossberg are both very popular and well made shotguns.
Shotguns, with pellets (not slugs) will not over penetrate passing into a neighbors home should the $**t hit the fan. You also don't have to really aim them for home defense, rather tuck it under your elbow, point, and shoot. Very effective.
Plus I've heard a deaf burgler can hear a pump action shotgun being loaded from a mile away and usually run in the opposite direction.
