How do I stop my dog from barking when he sees we are going to walk him?

when the dog sees us take the leash in hand he knows he is going out side for his walk and becomes very excited and therefore starts jumping and barking until we open the door to go outside.

You need to use psychological conditioning. Read up on the psychologist Pavlov, and more specifically his study named Pavlov's Dogs. Basically, you need to show your dog the leash, then when he barks, punish him some how (like squirt him with some water), but be careful, if you do it wrong, he might start to fear the leash. The important thing here is to reward him for seeing the leash and not barking, bacon works as a good reward to train a dog for this. Note: If you decide to spray him with water when he barks, you must do it while he's barking, otherwise he won't understand why he's being punished and will just be confused and scared.

lay the leash on a table near you, then call your dog and tell him to sit and stay. reward him for staying and continue to praise him as you keep your gaze on him while you reach for the leash. only grab the leash once he is listening to you. once he sees the leash he will start getting riled up. at this point put the leash back down and have him sit and stay. wait until he is sitting and quiet before you go for the leash again. if you continue like this your dog will eventually see that barking for you to hurry up isn't going to work. it will take a long time at first but if you are consistent with it it will become easier and easier. another thing to try if he is too distracted by the leash to obey you is to give him a treat when he sits and stays, but keep holding the treat with one hand while putting the leash on with the other hand. this way he is distracted and his mouth is busy while you are putting on the leash. if he stands up immediately take the treat away and put the leash down and start again.