In Goldeneye 007 for the Wii, there is a cheat you can use to turn on Tag Mode in local multiplayer.
Go to Extras and enter the following code exactly as displayed:
NotIt!!!11
Keep in mind that this code is case sensitive, and only works in local multiplayer games with three or more players. Once the cheat is entered, it will show up in the Modifiers list when starting a split-screen game.