Yes Muckmaw, you should be very familiar with a firearm (a class could not hurt, since you have no experience whatsoever) before keeping it around (and possibley loaded) for home defense. Learning to use cover, and knowing to not point the gun or put your finger on the trigger until you actually want to kill something, never hurts either.
And no its not as easy as a camera

Point and shoot, and you will probably miss. Shotgun or not. Stress, panic, and inexperience will make you do some really strange things.
Just get some practice and some tips from people that know what they're doing. Welcome to the "Gun Club" !

PS: Keeping it loaded will probably not hurt a standard pump shotgun. It does keep continuous stress on the magazine spring, would could freeze up and cause a jam, but its unlikely given the type of weapon . Well, at least as long as it hasn't been 20 years since it was loaded. The ammunition should probably be changed out once a year ( and you should practice at least that much). Choice of ammunition is very important as well. Personally I would reccommend a 2 3/4" magnum round loaded with No. 1 or "O" (single ought buckshot).