With interest rates low, go with a fixed 30 year. Try and put 5% down, and then take a 2nd out for 15%. You will pay a little higher rate for the 2nd, but you do not have to pay the mortgage insurance.
Make payments every 2 weeks. Don't make monthly payments, rather make payments every 14 days and you will knock off a few years on the loan, which will save you money over the long run.
Try to put as little down as possible becasue rates are so low. Property will almost always go up, so don't worry about being up-side down if you decide to sell in a few years.