Press space when you're at the level select screen to unlock all levels. Prisoners get angry slower. We could have done no anger etc but it would have ruined the game.
Death Row Diner Hacked
Your job as dinner lady is to keep these Death Row prisoners fed but also your job is to keep them killing each other as you try and complete all 21 days of this no reward job apart from the fact the customers won't be complaining about the food.