Depends on what you mean by best?
For instance, most dominant? For some reason the first two games that come to mind are the 2015 win over West Virginia in the Sweet 16, and the halftime score that same team had against UCLA 41-7
My favorite? 2003, Florida, at home. As a kid old enough to understand the game, but still young enough to cry when we would lose, that season as a whole was amazing. Say what you want about Dickie V, but his commentary that game adds to his legacy in such a positive way. To me, that game, atmosphere, and commentary are the epitome of college basketball.
Best win? Probably 2014 Wisconsin. That 2014 team had incredible talent. But that magical run leading up to the championship game is stuff of legend. 8 seed upsetting an undefeated team, allowing them to defeat their arch rival in the Sweet 16, only to win on a near buzzer beater in the Elite 8 against Michigan, followed by another near buzzer beater in the Final Four against likely the best team that year…shame they couldn’t close it out,
Honorable Mention: 1998 Duke. I was not alive in 92’, but I understand the importance of both of those Duke Elite Eight games. I was alive in 1998, and yet I’ve known for a long time it wasn’t just about winning a championship—it was also about healing from the scars of 92’. Three straight championship appearances is also incredible to be honest.