XBOX 360 Controller Question

I've been playing on PS4 for majority of my time with the game. I've recently switched to PC, and because I'm so used to using a controller, I picked up the XBOX 360 controller for PC. So far everything is great, with one minor gripe.

On the PS4 controller it was much easier to select things on the screen by pressing the giant touch pad button. On the XBOX controller it's done by the tiny back button.

I'm wondering if there is any way possible to make the big XBOX button do this task? The button isn't doing anything else in game.

Thank you for any help!