An information-processing device comprising: an object image displaying means configured to cause a display means for displaying an image to display at least a part of an object image group including plural object images in a size corresponding to a first scale; a display position change means configured to, if an operation means for receiving an operation instruction receives an operation instruction to change a display position of an object image of the object image group, cause the display means to display the object image group including the object image whose display position has been changed, in a size corresponding to a second scale that is smaller than the first scale, and thereafter cause the display means to display at least a part of the object image group including the object image whose display position has been changed, in the first scale size; and a processing executing means configured to, if the operation means receives an operation instruction to select an object image displayed on the display means in a size corresponding to the first scale, execute a processing corresponding to the selected object image, wherein the display position change means is configured to control how the display means displays the object image group, such object image group being a group of windows, such that: a first time period in which the display means displays the object image group in the size corresponding to the second scale is lengthened in proportion to either a number of windows displayed, or a difference between the first scale and the second scale, or an amount of movement of the windows whose display arrangement has been changed. an object image displaying means configured to cause a display means for displaying an image to display at least a part of an object image group including plural object images in a size corresponding to a first scale; a display position change means configured to, if an operation means for receiving an operation instruction receives an operation instruction to change a display position of an object image of the object image group, cause the display means to display the object image group including the object image whose display position has been changed, in a size corresponding to a second scale that is smaller than the first scale, and thereafter cause the display means to display at least a part of the object image group including the object image whose display position has been changed, in the first scale size; and a processing executing means configured to, if the operation means receives an operation instruction to select an object image displayed on the display means in a size corresponding to the first scale, execute a processing corresponding to the selected object image, wherein the display position change means is configured to control how the display means displays the object image group, such object image group being a group of windows, such that: a first time period in which the display means displays the object image group in the size corresponding to the second scale is lengthened in proportion to either a number of windows displayed, or a difference between the first scale and the second scale, or an amount of movement of the windows whose display arrangement has been changed.