Motion plus games require you to watch the motion plus instructional video prior to playing the game. If you have watched the video for motion plus from any other game then you will not need to watch it again.
To see the video you can simply use the original disc that you have and watch it or you will have to do some setting adjustments in your loader.
Each loader is a little different but they all allow you to load a different .dol for the game. Find this option in your loader and change the dol from default to player.dol After you do that you will need to load the game and watch the video. Once you have watched the video you will need to go back and change the dol setting to default.