It is a very good idea that you are having him neutered and I hope that solves some of this aggression.
IMO all male dogs should be neutered. They do not need those hormones raging thru them. Having him neutered should calm him a bit. But you also have to enforce training methods as he is acting as if he is the boss, when YOU are the boss.
When it comes to food, you need to make him work for his food. Teach him commands and make him do them before you place his food down for him to eat. Also, BEFORE he eats, YOU need to eat something in front of him, so he can see that the TRUE pack leader eats first and he eats when YOU tell him he can eat
