Unfortunately, Iowa doesn't allow rifle hunting, which doesn't make sense considering the ballistics of a rifled slug-gun. So that limits you to shotguns and muzzleloaders... or handguns if you want a challenge.
Speaking about Benelli's, the M1 Field Slug Gun in 20ga would make a excellent gun for a youngster for recoil and would take down a deer fine. Or even the cheaper version Nova pump.
I use a 12ga Nova pump (shoot's 3 1/2 Mag's) and have a 28" smooth-bore barrel -- for pheasant and turkey. I use a Ithaca slug barrel (Cabela's) for the deer season. The 12ga pump has a bit long pump action, especially for someone of smaller stature. Other than that, the Nova is very easy to clean, functions flawlessly and looks cool!
The great thing about both these guns -- the M1 or Nova -- they both accept the recoil reducer. The combination of the added weight and the inertia of the mercury filled capsule helps tremendously. The only downside is the small safety, the heavy trigger and the above mentioned item.
Also, both guns have aftermarket barrels that, along with the choke system, will allow you to alter the gun for most situations.
Of course, here in Iowa we have so many deer more people kill them with their cars than anything!
To sum it up, I can't speak on Beretta's, Remington's etc., but I'm sure there are some options there as well.