AutoFocus-Adding Picture for top of Blog without being in gallery

I want to create a gallery of images. I want the images to be smaller than the image at the top. How can I enter the top image without it being part of the gallery? You can see the problem on this blog entry http://www.reflections-etc.com/blog/open-house-pics/ The picture at the top has been added twice. Once at a smaller size and once at a larger size for the top.

Thanks