I agree with Phoenix.
Not your divorce, not your house, not your problem.
Now, your father is your father, and your brother is your brother, and your brother is your father's son--and their relationship is between the two of them. Not your problem.
Your impulse to DO SOMETHING is natural. If the situation were a fire or an earthquake or a hostage situation, doing something would be useful. Since the situation is an emotional tangle between your parents--and now your father and your brother--your role is much harder. You must MYOB--and that is all you can do.
What is going on in your own life that you can get completely involved in. You need diversion from family upheaval.
yMan - i can appreciate that you're worried about everybody, but they are all grown-ups.
As the doyennes have said so clearly - Not your divorce, not your house - I will differ slightly in that the fallout is already impacting you, and that is a problem for you. But what happens to the marriage and the house is their business.
I'm still a little concerned when I look back to your initial post, and read again that you had to be prevented from getting physical with your brother when you felt he hadn't been appropriately deferential to your father (or at least that's my read of it).
Maybe you would benefit from some counselling to help you get over the stresses in the family as the divorce/family split becomes more imminent.
On being deferential to either parent -
I think respectful tone of voice to everybody - and from everybody - is important. I am not a big fan of sarcasm or taunting when speaking about an issue, much less yelling, but it is a life long process for folks to learn to speak their mind without being that way. People will see the same situation differently quite often and sometimes have so much emotion about it and so much time invested in thinking one way about it, that simple discussion of different opinions is hard to accomplish without rancor.
I was raised in a home where I was never allowed to "sass", which seemed to be defined as answering back at all. Sometimes it is smarter to not answer for a moment, but not in the long term, because then communication dies. Your brother and father, and mother and father, all will have some communicating to do. I don't think you should be mad at one or the other for losing their temper and saying nondeferential words, as it is hard not to when one is very wrought up about another person's point of view, especially when it affects your life.