The answer would be all of the guns listed, depending on the species and location of the hunt. For me, it's mostly deer, and with buckshot in the swamp with the dogs running the deer, I'll usually go with a Remington 1100 2 3/4" .12 gauge with a modified choke tube and 00 buckshot (having 5 shots is sometimes a necessity in the swamp). If we're running the dogs in an area where long open shots are a possibility, then it's a Mossberg 935 .12 gauge loaded with 3 1/2" 00 buckshot and full choke tube. If we're driving some light, open hardwoods, then I might pick my Beretta 3" .12 gauge loaded with 1 buck, again with a modified choke. Turkeys I use a Charles Daily .12 gauge pump with an X-tra full turkey choke and 3" #5 turkey loads (6 shots, since we can kill two gobblers per day, down here). Dove, quail, rabbits, and squirrels, then it's time for the Stoeger .20 gauge O/U, and an open and a modified choke, or a Mossberg 500 .12 gauge with a fixed modified barrel.
That's why I'm a firm believer in having more than one gun, since I like specific guns for specific types of game and conditions. We won't go into rifle choices, since that wasn't in the original question.