Hit the Spot!
Stand back on the 'player point' and fling-toss the disks, aiming to land within the outline of the circles. Player with the most on target wins (keeping score). Can have a 'play-off' for multiple winners. Or make your own rules eg. maybe have 3 shots each, with the 4 discs. Or for more difficulty, player has to nominate which colour target he is aiming for.
Degree of difficulty is determined by the distance of player from the board.