You should make darned sure that the AOA internship is approved by the ACGME advanced residency before going that route. Advanced residencies have no obligation to honor the rotating internship as equivalent to an ACGME TY/prelim year, and many don't. I know if I were a program director for any moderately competitive advanced residency I would have a huge problem with a D.O. who did their internship at some osteopathic hospital in the sticks somewhere.
Resolution 42 petition=an application to be filled out and mailed to the AOA.
Rotating internship= a year of being a scut monkey for little pay and no respect.
From my point of view, the Resolution 42 route makes more sense to me.