My pick would be Romo's TD to Williams in the Detroit game before the half.
Some of the other plays were either not as important at that time or partially due to the effort of the WR. The offense was stagnant against the Lions which had a great Run Defense, Free was out and Murray was banged up. We just got screwed on the play before where we threw a bubble screen of sorts to Witten for the first down on 3rd and 3 (IIRC) as the refs called a bogus holding call on Williams.
So we desperately need to score and it's 3rd and 13 and Romo hangs back in the pocket and fires a strike to Williams right at the time a Lions defender hits him and Williams takes it to the house. Most of the time, any QB would have trouble with that play because they either couldn't get the throw off or throw it accurately enough. Williams was more or less in the right place and was able to go in for the TD, untouched. Had the throw not been on the money, that would not have been the case.
YR