RE: arrow questions
Couple suggestions. #1, once you get into bowhunting you will stay at it. It's addictive. So don't worry about that part.
Secondly, I think you need to take the bow to a local proshop and see how well it fits you for draw length and see if it can be adjusted for you. Many people unknowingly shoot a draw length that is several inches too long for them. Thus they never achieve a level of competancy that they are capable of. Being honest, if the bow is a 31" draw then you'd need to be about 6'5" tall for it to fit you somewhere close to right. 6'2" to 6'3" for a 30" draw. There's more to it than this, but this is just to give you an idea. Draw length is the most important feature of a compound bow.
You can't learn any of this stuff at WalMart. Find a local proshop and get fitted correctly. It'' make your learning a lot less frustrating, and probably cheaper along the way.
Enjoy.
Barry