Konami Classics Series: Arcade Hits Cheats :
Code - The Konami Code
After selecting Gradius from the main menu, at the title screen put in THE CODE - Up, Up, Down, Down, Left, Right, Left, Right, B, A - and you should hear a noise confirming that it has been entered. Start a game as normal, however upon starting your game press the Start button to Max-out your ship with every power-up, except for Speed. You can only do this once, so make it count!