Change Display settings
This allows you to change the size of the display and how to change which way your mouse scrolls across the screen.
Anywhere on your desktop, right click. This will bring you a sub-menu where you can click on Display Settings.
Click on Identify to see which number correlates to which screen is shown in 'Rearrange Your Displays'.
To change which way the mouse goes, simply drag the numbers (click and drag using your mouse) to where you want them to be when moving your mouse.