I would go with the 30 year mortgage since the payments will be lower each month.
You can always pay more money towards the mortgage when you want to if you want to pay the mortgage off sooner than 30 years.
With a 30 year mortgage you can lower your payments and still keep your house if you have a sudden job loss or other loss in income.
I've read that some people have paid off a 30 year mortgage in 5 years by saving on other things and putting that money towards the mortgage payment.