I agree with Power about the pump shotgun being the best but when you are talking about being involved in a very tense and fearfull situation I believe that most people will be better off with a double action revolver as there is no safety to fool with and no chambering of a round to remember. More experinced shooters can take the necessary actions of semi autos and pumps but someone thats not going to shoot and handle the firearm on a regular basies should stick with whats simple in a tense situation. IMHO.