The absolute safest mortgage is a 15- or 30-year fixed-rate loan. (The interest rate never changes, thus the fixed.) Another option is known as a hybrid mortgage. The typical hybrid is 5/1, 7/1, or 10/1, which means the interest rate is fixed for the first period (be it five, seven, or 10 years) and then converts to a rate that can change every year. The advantage of a hybrid is that the starting interest rate will be lower than on a fixed-rate loan. And if you move within that initial period, you won't be hit with an adjustment (but make sure beforehand that there are no prepayment penalties).