i know that it has been said that you can plant corn and beans by broadcasting them, but i would think that if you can't get any equipment in there to plant them below the surface, you're better off working with something that is meant to be broadcasted. again, i'm not saying that broadcasting corn or beans is a bad idea, just seems that you could lose a lot of your investment that way not knowing how much is going to 'take.' i would look into some variations of perennials and annuals that you can broadcast. sounds like you have a decent area. maybe put 1/4 to 1/2 of it in a perennial like clover, and then the rest in annuals.
as far as the the rocky area....it all depends on how big these rocks are! [:D] if you can, and it's not too much work, try taking them out a little at a time....but the thing with that sometimes, is that you take them out and then more pop up. nature of the beast in an area like that. so, if they aren't that big, you could broadcast more plots in there if you want...take a 4 wheeler when you're done with some kind of drag behind it and go over it a few times and you should be good!