You really, really need to get a lawyer in your state who knows the laws specific to your jurisdiction. Divorce laws vary a lot from state to state. Seriously...I'm a lawyer, and honestly one of the worst things in the world is to see people make mistakes because they try to avoid the cost of a legal consultation. PLEASE don't do this to yourself when so much is at stake.
With that said, one thing you might want to consider is that retirement assets such as 401(k)s aren't really worth their face value--they are worth their face value MINUS the taxes to be paid upon withdrawal. So a $100,000 house and a $100,000 IRA (unless it's a Roth) are not really an even trade.
Of course this works in your favor here. But it's something to consider.