Scooby Doo: Night Of 100 Frights Cheats

Pause the game and hold L and R, then

X,X,X,B,B,B,X,B,X
Unlock all FMV's

B,X,B,X,B,X,X,X,B,B,X,B,B,B
Unlock all power up's

X,X,B,X,X,B,X,B,B,B
Unlock all warp gates

X,B,B,X,B,X
View Credits

First go to smugglers cove then go to shock on the dock part II. 
There is a pile of planks near the warp gate.  Do a thunder smash
on it and then you will get to creepy crawlies in the hallways. 

Change the Xbox system date to one of the following entries to see special things at the front yard and the mystic playground:

Red Beard will send out ghosts. Dodge them, then a ghost of Captain Moody will appear. He will throw his sword. Go to one of the ropes, stay until the knife cuts it, and keep repeating this attack.