Should you do something silly and your screen settings get all messed up, just tap Ctrl+Alt+Shift+F12, and you’ll find yourself back at the default resolution of 640x480x8bpp.
One nice feature that Be has thrown in the Screen preferences panel is the ability to adjust position without using your monitor controls. With the panel open, hold down Ctrl, then tap the arrow keys to move your screen in the desired direction.
Don’t worry about the safety of this maneuver: Modern monitors will shut themselves off if they can’t handle the instructions you send them. Just undo the action you just did and you’ll be fine!