Depends on what the laws are for you. I'd like something fully automatic for this reason, but anti assault weapons people on their high horse seem to think people aren't responsible enough for them. But a 9mm with a regular capacity is plenty for home defense. I use everything though...
For home defense each family is different.Ther are numerous factors to consider. Firstly, what are you protecting yourself from? What is the level of danger where you live? How much do you have in your security budget?.For example, for non dog lovers a dog is a major maintenance issue. Remember a home security system is "an annunciator". It will not "protect you".. It only lets you or a monitoring company know someone has breached your perimeter. A gun is extremely dangerous for the average family. It should require training for all and security for the weapon itself. A baseball bat is great if you know how to swing one, some folks have a hard time with one. What do you need to feel secure? Secondly look at you home as an intruder would. Find your weakest spot and work from there.
I'm personally use a pepper spray it's very handy and u can carry it with you everywhere you go just check your local laws if you can carry one and practice at your backyard with a piece of cardboard with a face drown on it and believe me it will give you enough time to run away or call police ;-)
Metal bat and full force paintball gun and some gum to grab and chew while beating the hell out of the person who broke into your home or shoot numerous times with the paintball gun. And possibly making them very bright and colorful looking... PRETTY COLORS.
Shotguns at close range doesn't spread that much and that sound that everyone scares ppl away doesn't always scare them if they have a gun and in close combat it's harder to shoot someone so a handgun like 9mm would work just fine