Go to the "Continue" screen and enter in one of these codes:

Venom Defeated(2nd time) - 475L
Hobgoblin Defeated - 6QSP
Lab - X--8L
Last Level - 58---

"NOTE"- I have this game, and I assure you that these cheats will make your progress at least 70% more efficient than the leading cheat sites (who don't have the game and copy from each other with permission)