My boyfriend is 2 years older than me...we're more or less on the same page as far as life goals, where we want to be, schooling, etc. I totally was NOT looking to settle down with one guy the day after my 18th birthday and he had, at 20, already planned on spending his life with two other girls (one he was VERY young, only 16-18, one had just been that past year) but hey, i guess if you find the right person you don't want to look for anyone else and it just makes sense.
I would absolutely date an older guy. And right now I'm only 19 so it wouldn't make sense to go younger, but in the future i would. I think as long as you're in a similar place or where you are in life compliments where the other person is, it's fine.