How Does an 80/20 Loan Work, in Terms of Refinancing?

refinancing

In May of 2003, my husband and I bought a house. We got an 80/20 loan to cover the cost. 80% of the loan is a fixed 5.25% rate. 20% of the loan started at 6.25% and currently sits at 9.25&. The loan is going to readjust next May. Is the 20% loan considered a second mortgage? How can I refinance it now and get a reasonable rate? My husband and I have near-brilliant credit.
P.S. as a side note, the house we have the mortgage on is currently worth roughly $20,000 less than we paid for it, so rolling the loans together is out of the question.