Humping and aggressive behaviour

Question
We have a 4 1/2 year old Golden Labrador retriever.He was neutered at age 2 years and 3 months. ( 1 testicle is undescended and the vet left it at that)He continues to hump one of our housemaids and almost any female visitor to the house. He has also become so aggressive that he barks at all our visitors catches them for humping and barks non-stop. we recently shut him out in the back yard and he barked non-stop for 4 hours and tried to break the doors down. We simply can not invite any one home. He is very loving towards the family members and does not trouble the maids at all when we are not at home.He walks on a leash outside the house and is calm. We are at our wits end??Please help.He is our first dog and may be we pampered him too much.

Answer
I don't like leaving the undecended testicle especialy since you are still having behavior problems.  I would check with another vet on it.  He also needs obedience training.  

The key to most behavior problems is approaching things using the dog's natural instincts.  Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog.  Life is much easier if the 2 legged pack members outrank the 4 legged ones.  You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/  For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm

Go ahead and restrain him when you have visitors, keeping him on leash, on tie down, or in a crate.