At the top of your payment priority list: Remit to the U.S. Treasury the required withholding for employees' federal income-tax and Social Security / Medicare tax. The IRS will come for your house if you don't.
I wrote a comment here about how the IRS is actually not that unreasonable when it comes to owing more than you can pay (been there, too!), but then reread DC's comment and saw that he's talking about withholdings for employees. Yeah, don't fuck around with that.
2nd that - my parents lost their business. Before they did, their idiotic "accountant" lied to my dad about having paid withholdings. They went into receivership actually owing a great deal in taxes that they could have paid (they paid other creditors first). My parents lost everything and are still in deep trouble w/ the IRS. Pay your taxes before anything else.
