On the title screen on part two, type "BRUISER" for infinite lives.
Right at the beginning of the game (blue sector) you will find a well on the left. Run towards it and jump before you hit the wall. Now you will find yourself at the other side of it. Keep on walking to the left and you will notice the screen going crazy. Waggle the joystick in all directions and after a while you will find yourself in the red sector. Once in the red sector do the same as in the blue sector. Now you go to the purple sector. Do the same as in the red and blue sectors. A message appears that you have completed game one and the code word for game two.
2-"SABATTA"
3-"PORSCHE"