Have you ever had the problem where you inadvertently moved a window outside the
boundaries of the screen? Or your display was stuck in a very low resolution because
the Display Settings dialog box was bigger than the screen at that resolution?
There's an easy way to move a window without using the mouse; by using the
keyboard arrow keys.
Right-click on the problem window's icon in the taskbar and, in the popup menu
that appears, select Move. Then use the keyboard arrow keys to move the
window to a position where you regain control of it.