Victor managing to bring Sparky back to life. Which is not a spoiler because it's the entire premise of the movie and audiences knew going in that Sparky would get killed somehow and then be brought back to life, but it's a Crowning Moment of Awesome for any viewer who's ever had a pet die.
Victor saving Elsa from the burning windmill.
Victor's father giving Victor the confidence boost needed to bring Sparky back to life a second time after Sparky dies in the burning windmill, deliberately sabotaging his own previous lesson about moving on in order to be there for his son when his son needed him.
Victor managing to hit the ball on his third attempt during the game. Too bad this is what led to Sparky's death.