A touch screen device and method of displaying images using display windows and selecting execution menus displayed on the display windows in a touch screen device are provided. The touch screen device includes a screen, a display configured to display images thereon and a detector configured to detect a touch on the screen, and a controller configured to control operation of the touch screen device in accordance with the screen touch detected by the detector. The controller causes two or more display windows to be displayed in an overlapped manner. Further, if the touch is detected on an underlying display window covered by an overlying display window, the controller causes a display form to be changed in response to the touch. That is, if a touch is detected on the display window covered by the overlying display window, the touched display window is displayed as an overlying display window.