You can prevent the other side from getting any runs by pressing 'Esc' when the opposing side's batsmen begin to run. They'll be stopped before they reach the crease and the game will continue with the start of the next ball without any runs having been scored.

When batting, to get a lot of runs press 'P' when the fielder picks up the ball to pause the game. The fielder will be frozen, but your batsmen won't. Simply waggle the joystick and your batters will run. You can now chalk up a high score. When you've had enough simply press 'P' again to unpause the game.