Lego Island 2 Cheats

Grinding
Go up to Space Mountain. Press [Left Ctrl] to get on your skateboard. Then, while on the skateboard ride off the side of the mountain at the space port (not the rocket ship, but where the building is located). Do not turn until you are on a brown piece of land. Once there, turn left and go upwards to the side of the railroad tracks. If you are in the corrected position, you will grind the tracks. Note: Several attempts may be needed.

Walk on water
Get on your skateboard. Hold [Left Alt] to jump while you are riding towards the water. The grassy area near the Res-Q HQ would be a good place to try this trick. Just before you fall in, release [Left Alt]. If done correctly, you will see Pepper put away his skateboard just as if he were on land. Press the cursor keys to walk on water. When you are ready to return to land, you will see Pepper fall into the water and get back out.