Abstract: A method and system is implemented on a host computer for operating upon a window system to update a graphic representation of a selected window item using an image information reading apparatus. The invention mainly includes an image cropping manager for providing a cropped image by cropping an image transmitted from the image capturing manager according to a size requested by a user; and an interface manager for providing a plurality of menu items each associated with at least a dialog box for setting the cropped image as a default image of a selected menu item. The plurality of menu items include Startup Screen, Wall Paper, System LOGO, Icon, Cursor, Screen Saver, Shutdown Screen, Theme, and Restore for updating an associated graphic representation. Eventually, an user can easily establish a personalized windows graphic environment with the assistance of the invention.