I think it is amazing the effect that color can have on the tone of an image. In the first image, in black and white, there is a certain degree of humor, but not joyously so. Maybe it is cynical humor.
In the second image, I think the boisterous color allows the humor to show through. Perhaps the vibrancy of the color relays some of the life inherent in the laughing ?
Do you have a preference? Which speaks more to your idea of humor and laughter?