Hi Raulin,
Basically, in my mind, for the first time shotgun buyer it boils down to one of two pump action shotguns; either the Remington 870, or the Mossberg 500/590. The Remington has been around a little longer and is used extensively by police and military, but the same can be said about the Mossberg. Both are excellent guns. I prefer the Mossberg and own a 590 w/eight round magazine, Galco buttcuff and TacStar side saddle. This weapon will hold and carry 20 rounds of 12 gauge ammo, more than enough for any problem you're ever gonna face in or around the house (and have any realistic chance of surviving). The reason I chose the Mossberg over the Remington is because both of the Mossberg's controls (safety and slide release) can be operated by the strong hand without moving it from the trigger position.
If you decide on the Mossberg I suggest the 590 with the "regular" trigger, NOT the "double action" trigger which duplicates the trigger pull of a revolver.
Coolio