Man, you sure ask a lot of questions,

, but lets see if we can answer them, as for a list of public land, on the NJDEP website, there is a list and maps of all the WMA's, most are huntable, but obviously, your equipment will factor in, you dont really want to hunt a fast moving river from the shoreline, as far as individual WMA's like the wanaque, the best thing is to go to them and scout them out before the season, and see if there is an office there, where they can give you specifics, but there is plenty of open public land, i hunt nothing but public and usually during the week, and most of the time i am the only one there. You shouldnt be that far from sawmill ( watch the currents) or even Raritan bay, which is where i spend most of my time for the coastal zone. A lot depends on how far you are willing to drive, i'm not above leaving my hous at 2 in the a.m. to hunt ABsecon bay in Atlantic city, and i dont live far from the DEl water gap. I dont really know all the gun models that well, but your mossberg should be fine, i do suggest a gun that is parkerized, they are pretty much always getting wet and if you hunt coastal you have the salt to deal with, me, i use a Browning 10g BPS steel spcl, for retrieving birds, a kayak is fine, alot of guy's use them, just pay attention to the water conditions your putting into, always SAFETY first, and the birds will flaot pretty much forever, ducks feathers are waterproof. Last but not least , IS IT ADDICTING? man, you cant imagine, once you get into it, you wont want to do anything else, i have spent my whole life hunting everything in jersey, but i spend more time on ducks than all other hunting combined. Anyway, i hope some of this helps, hook up with me near the beginning of the season and we'll get you started.
Just once i would like to hear you scream in pain !....wanna hear me scream in pain? Play some rap music!