> Go to the Options Screen.  Select "Platform Only".  Hold Left on the pad while pressing B over the following numbers: 1, 7, 1, 6, 7.  You should here a louder beep when you press B the last time.  Next, set the game up the way you wish.  Point to the number of the stage you wish to start at and hold Left+B to start at that stage.  Note: there is no stage 7 so that takes you to the Title Screen.

> Go to the Options Screen.  Select "Driving Only".  Next, hold Left and press B over the following numbers: 1, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 1.  You should here a beep confirming the code.  Now during any game, press Start to pause and C to skip to the next stage.