Sega Master System Cheats - The Flintstones

Level select:

Press Up, Right, Right, Down three times, Left four times at the title screen. Then, press Pause and hold 1 + 2 when game play begins. Press the D-pad in one of the following directions to begin game play at the corresponding level.

Level --- Direction 

1 --- Up 

2 --- Right 

3 --- Down 

4 --- Left