How do I set which layout the game will start on?

I have no clue how to do this... I need to make sure when people load my game it will start on the title screen, how do I know which one it will start on?

In the Projects panel click on the name of your project (at the very top of the tree.) This brings up the project properties in the Properties panel. Then change the First layout to the layout you want to be first.

(Alternatively you can click on the layout to bring up the layout properties and toward the bottom of the Property panel you'll see a link to the project settings where you can change the first layout.)