i would try using the cesar millan train methods to help you show to him that this is your house and you will not put up with naughty behavior it is much like being the leader of a dog pack would treat him if he acted out. i have forun that this is very help ful but also take him to the vet and get him shots and get him nutered i have found that in aggressive dogs if thay are spayed or nutered most of the time it will calm them