Robin and Batman's first meeting and subsequent night on patrol switches between this and Crowning Moment of Funny more times than one could count.
The song "Dynamic Duet" is cheesy, but in the most heartwarming way possible. Seeing Batman finally happy is enough to bring a tear to one's eye.
Batman checking the results of the Facebook poll... and it's a unanimous vote to save Robin. Even after he was the Scrappy to the people of Gotham, they decided that if Batman liked him, he couldn't be that bad.
Superman and Batman (and Robin) deciding that they should be... Super Friends.