There are significant pros and cons to the defense shotgun.
Especially for a novice. They require two hands to opperate making it more difficult to try to open doors or speak to 911 on the phone while armed. The added length of the weapon makes it cumbersome in tight confines such as hallways or doorways. Bird shot is known and proven to be a very poor fight stopper in countless actual gunfights. I've personally tested birdshot fired into soaked newsprint at 21ft and under(realistive defensive shooting distancts). Soaked print gives a very accurate test of bullet performance and penetration. In my test with typical light game birdshot(#5 through #9 shot size) I've seen penetration as little as 3". Compared to the normal desired 10"-12" of penetration recommend for a defensive rounds, and I'd say that is pretty unfavorable. Once you get to #4 sized shot and above you start to see some better results. With all but a few exceptions most slugs on the market will penetrate walls FAR more than any defensive pistol round and even many rifle rounds(mass in motion after all... most slugs weigh at least 1oz). 00 or 000 buck is very effective and splits the difference well between the dismal pentration of bird shot, and the massive over penetration of most slugs. Its hard to argue against 6 or 9 .36 caliber lead balls being sent at roughly 1200fps.
As to the racking of a pump shotgun being a deterrent to criminals, and striking such fear the they virtually wet themselves or go fleeing into the night... All I can point out is if the son of bitch was bold enough to enter an occupied home intent on crime(rape, murder, burglary, etc.) what makes you think that noise is going to scare him off... and great now the bad guy nows exactly where you are when he hears you rack that pump.
