2-Up in Hot Head Hop
In the level 'Hot Head Hop', throw your partner right above the entrance. If you look closely you will see a black treasure box. Pick it up and throw it at the first rat. The box contains a 2-Up.
At the gameplay select screen highlight the Cheat Mode option and press Y, A, SELECT, A, DOWN, LEFT, A, DOWN.
All 75 Kremkoins
To see the best ending, you must have all the DK coins and found all the secrets. Once you've done this, beat all the LOST WORLD stages and the crocodile head will open in the middle of the LOST WORLD. Enter it for the special ending.
To activate cheat mode, enable the Music Test, then press Down repeatedly until Cheat Mode appears. At this point you can gain 50 lives by pressing Y, A, Select, A, Down, Left, A, Down. To eliminate the DK barrels, press B, A, Right, Right, A, Left, A, X. Now start the game. If you did this correctly you should get Diddy and Dixxie Kong whenever you start.
To check how many DK coins you have at cranky's video game heros place do the following:
At the map screen press L,R,R,L,R,R,L,R,R (the top buttons)
until a screen comes up that says "cranky's video game heros".
In Krazy Kremland, at the very beginning of the level "Hornet Hole", let the other character climb on your back. Throw them Up and Left to find a hidden hook. After that, climb a wall of honey. At the top are 2 hidden bonuses.
Start a new game in two-player Team mode, them press Down repeatedly until a Music Test appears.
No DK Barrels
At the gameplay select screen highlight the cheat mode option and press the following buttons:
B, A, RIGHT, RIGHT, A, LEFT, A, X (BARRALAX)