Sorry, but according to the guidelines, I'm not allowed to put the Windows 7 logo on the start button, but wikipedia has a Windows 7 logo you could use at http://en.wikipedia.org/wiki/File:Windows_7_logo.svg The task bar icons on the right are available individually in my collection at http://openclipart.org/collection/collection-detail/mightyman/6246 I did not draw the Open Clipart logo in this image, I found it in the Open Clipart library.
