Each of the games has it's own specific settings. These are mostly to do with the rules for the game, so you can choose to have it play the way you want it to!
Here's the settings icon for individual game:
Tap the Cog icon to expand and show all the game settings, then choose the options you want for your game.
The game specific options page
It will remember these every time you start a new game without you having to go in and select them, so it's even faster to choose another game of the same type. If you want a different setting - perhaps to make it easier or harder - just tap the cog to make your choices, then tap the Play button to start your game.
Note that there's an option in there to turn on or off Move Highlighting as this is a feature that some people love and some people dislike - here you have the choice!