O.K here's an explanation of what the games are and what they do.
Jump Game - (you get this when your a baby) You have 3 circles above your tamas head. When one fills in you have to hit the button. EXAMPLE : If the circle on the right fills in hit the button on the right. You have to hit it really fast to win so you need quick reflexes.
Bump Game : (you get this when your a toddler) You go against another tamagotchi character, and you face back to back. When the top of the screen says push, press the B button (middle button) and a power meter shows up. Try to get as much power as possible and bump your opponent over. It helps A LOT if your tamagotchi is fat.
Heading Game : (you get this when your a teenager) Your tamagotchi is in the middle of the screen and a ball falls from the sky. Try to go back and forth through the screen and pop the ball back up in the air. But a tip is after you hit a ball make sure you go back to the center of the screen so you don't have to run across the whole screen to bump it back in the air, you usually don't get there in time.
Slot Game : (you get this when your an adult) You have to bet on a certain amount of gotchi-points then a slot comes up. Press the B button at any time and hope it lands on something that doesn't look like a X. This game involves much luck.