Spinning Kong is Donkey Kong's Up B move in all of the Super Smash Bros. games. Spinning Kong is best used for a horizontal recovery, though it does go slightly vertical. It is not very reliable, even though it's horizontal distance goes almost as far as Meta-Knight's Mach Tornado, because of it's poor vertical rise.
When used on the ground, the Spinning Kong can be used in a fashion similar to Bowser's Whirling Fortress; it can be used out of the shield, or as a disruptive tactic. The Spinning Kong's first hit, in which Donkey Kong extends his fist to charge up the spin, has decent knockback. It also has some invincibility frames when it first comes out, making Donkey Kong resistant to knockback.
He has yet to use this in any non-Smash Bros. games.