The present invention relates to a method and apparatus for controlling an image scanner which is connected to a computer and adapted to scan an original document image to generate image data of the document image and storing the generated image data in the computer. A recently-developed image scanner (scanner) has a function to store the scanned document image as a file in a computer. To store the scanned document image as a file in the computer, it is necessary to control the scanner to scan the document image at the resolution, scan speed and in the color density of the desired original document image (hereinafter referred to as "scan conditions"). Scanner controls, including a scan starting function for initiating a document scan, a progress check function for checking whether the scan has been started, a position return function for returning the original document at the desired position, and a color density changing function for changing the scan density of the original document are also well-known. For example, in one type of image scanner, a keyboard is used for generating a document scan request to the scanner, and a display screen is used for displaying the message indicating the scan status of the scanner. A scan starting button, a scan speed button, a color density button, and a position return button are usually provided on the scanner. When a user selects one of the buttons and then actuates it, a request for starting the scanner operation is sent to the scanner. In response to the request, the scanner executes its operation by performing the above-described controls. As can be understood from the above description, in a conventional control method, the scanner controls (a scan starting function, a progress check function, a position return function, and a color density changing function) are provided separately. Therefore, to select these controls or to use them, the user must operate the various controls through the keyboard and then visually check the display screen. When the scan starting function is used, for example, the progress check function is switched off. In this case, when a plurality of documents are scanned, the user must perform the following operation: While the scanner detects the presence of documents, operate the scan starting button. However, this operation is a troublesome, and it is also difficult for a user who is unfamiliar with the operation of the scanner to operate it. As can be understood from the above description, in the conventional image scanner, the scan starting function, the progress check function, the position return function, and the color density changing function can be controlled separately. When a plurality of documents are scanned, therefore, the user must select each of the functions independently and thus it is troublesome for the user to use the functions. Furthermore, when the user wants to change the scan conditions from the default conditions and set the scan conditions to the conditions for storing a document image, the user must confirm the conditions while looking at the display screen and then actuate the scan conditions selecting buttons while changing the conditions with the button keys. This operation is troublesome for the user. The above-described problems are not limited to an image scanner but also are inherent in a device which processes the data obtained by scanning an original document and generating image data.