I was looking on IGN for the cheatcodes relating to 007 Goldeneye wii and came across this (The Cheat in bold below):

Cheat List

These case-sensitive codes can be entered in the Cheats section of the Main Menu for the desired effect.

NotIt!!!11 - Unlock Tag Mode (Local Multiplayer) / Toggle on in Modifiers menu / 3 or more players required
Inv1s1bleEv3ryth1ng - Unlock Invisibility Mode (Local Multiplayer) / Toggle on in Modifiers menu / Hold SPRINT to toggle Invisibility
477MYFR13NDS4R3SP13S>
- Unlock Big Head Mode (Donkey Kong Mode) in Local Multiplayer. To switch it off, reset defaults.