You can use the shortcuts to program a setting you prefer with AC off, vents closed, fan on/off, certain temp, etc. That's about the only way. It will always auto revert to vents open with AC off and vents closed with AC on.
Funny, My 2G TL does have that A/C with Circulation ON odor that smells funny after a while but my 2G MDX does not..
I can do all day with Circulation ON without having that odd smell come through, Perhaps is the active carbon filter I installed?
In any case we have a lot of smog here in SoCali so having the Circulation Off is not sensible.
^^^What, do you drive to an alpine meadow, air out the car and then drive to work? ;-) Within and hour I would have polluted the air to the point it would rank worse than Xingtai, Hebei province in China.