Level Select
     Enter  G0LVL (G'zero'LVL) followed by the level you want to start
at.  Now  ACCEPT.  The  message  "Cheat Activated" appears, and select
Quit.  Then  start  a  new  game. Now, you will start at the level you
want. The levels go up to 34 and 35 is the ending cinema.

Access All Weapons, All Levels, Invincibility and Unlimited Firepower
     Enter  1GOTP1NK8C1DBOOTSON  at  the  password screen. The message
"Cheats Enabled" will appear if done correctly.