Take safety course
Shotgun either single or pump
Mossberg and Remington are both good brands
.12 guage
buy less lethal/bean bag ammo for home defense, also some snap caps and some buckshot
also, should someone break into your home, you should only rack them weapon and tell them to get out. Taking a life should be last resort choice if your life is threatened. If they run, let them. The minute you kill them, it goes from self defense to murder/manslaughter.