This probably isn't specific to a Dimension computer.  But, all I'd like to do is change the function of the scroll wheel button and that option isn't available under the mouse properties.  You can only change the function of the left-right buttons, or the number of lines to scroll.  With the MS Intellimouse, you can make the scroll wheel button do any of a number of functions.  I tried installing the MS Intellimouse 6.1 version, but it won't work with Dell's optical USB mouse.  Having the button allow you to scroll by moving the mouse is kind of useless.  Being able to minimize an active screen would be nice though.  Anyone have any ideas versus buying a new mouse for such a rather minor improvement in function would be nice?