Saiyuuki World

Continue

When you return to the title screen after a game over, hold down and press start to continue at the level you were on.

Fully Powered Up & Level Skip

At the title screen, press Up, Down, Up, Down & A. If done right, you'll have a high jump, 99 bolts, better shield and unlimited money. To skip levels, just press Up, A & B at the same time.