All Working Scooby-Doo! Classic Creepy Capers Cheats - Nintendo 64

Unlimited courage
Enter the following code during game play while controlling Shaggy, but not in the inventory or options screen. Hold [L] and press [C-Up], [C-Left], [C-Down], [C-Up], [C-Down], [Up], [Right], [Down], [Left], [Up], [Left], [Down], [Right], [Up], [Down]. Shaggy will say "Wow" to confirm correct code entry, and his health bar will now be blue.

Level skip
Enter the following code during game play while controlling Shaggy, but not in the inventory or options screen. Hold [L] and press [C-Up], [C-Down], [C-Up], [C-Down], [Up], [Down], [Up], [Down], [Left], [Right], [Left], [Right].

Museum: Defeating the knight
In level 1, find all the clues, then keep using the fire extinguisher on the knight.

Museum: Finding Velma
Go to the prehistoric wing to find Velma. There are a lot of dinosaurs that will scare Shaggy. Try to avoid the swinging objects. When you find Velma she will need her glasses. To get them, you need to go to the Egyptian Wing.