No, the goal you pick to defend in the 1st is the one you defend in the 3rd. It doesn't change after halftime.
Before this deferral stuff came into being, when the wind was going to be really a factor, smart teams that won the toss gave the loser two kickoffs in exchange for the wind at their backs in the 2nd and the 4th quarters.
People make cases for getting the ball first, defending first and so on, thesedays.