Boston also plays with a DH. So their OPS+ of 107 is helped with the DH, as well as having Ortiz and Manny. Like I said 1-9, they have a better lineup.
The other two, I'm pretty sure Colorado had like the best 2nd half pitching in baseball, while Boston had Matzusaka, Wakefield, Okajima, and Gagne breaking down.
As for defense, Colorado plays in Coors Field, a tougher place to play defense in, and they've excelled.