You're way too young to be worried about 30 years vs. 15. Do the 30, pay extra every month when you can, any extra goes straight toward principal.
That's why I went with the middle of the road approach, the 20 year. Saving a bit of interest compared to the 30 year, but without the high mandatory monthly payment of a 15 year.
I usually like middle of the road on most things.
