I looked at the 15 year and 30 year options with a $200k mortgage.

30 year: $1074

15 year: $1492.

If you pay the 15 year mortgage at $1492/month for 15 years, you get a paid off house in 15 years.

If you pay the 30 year mortgage at $1074/month for 15 years, you've paid off $65k, but you can invest $418 monthly. At 7% (a low but realistic rate for a diverse index fund), you would have $132k saved. This puts you in pretty good shape and by the end of 30 years, you would be way ahead.

30 year mortgage and invest the difference. You're also protected against loss of income, because you end up with greater savings.