If we get to actually make a difference in the game ... I'd go into the 2007 SEC Championship and catch one of Ainge's two second-half interceptions, setting us up to score and tie the game at 21-21, instead of losing 21-14. That'd put us in overtime, and the Vols are usually money in overtime. We'd win the SEC Championship and end the season 11-3, ranked in the top 10, having gotten one more SEC Champ trophy out of the Phil Fulmer years.
If we don't get to actually make a difference ... I'd pick the 2006 'Bama game, last time we beat our nemesis in Neyland Stadium.
EDIT: I'm changing my vote. If we don't get to make a difference, I'll take any game with General Neyland coaching. Would love to experience that gentleman's leadership live and in color.