[fogebotom]

Rather then muzzling the dogs, they need to have timeouts-seperated in different rooms or put in their crates. Make sure you do it to both dogs, regardless of who started it. By the time the fight is going on, they don't really care nor remember who started it, just that they are going to finish it. It's up to you to finish it.

Also I think you are on the right track with the human vs dog issues-it's you who needs to be in charge. You might want to do some research on NILIF or Nothing in Life is Free. Time for some tough love, which in the end should bring you a more harmonious household.