I've been working on it so that when you click on a thumbnail, if the displayimage page is long enough to require a scrollbar, it would automatically scroll to the top of the image. That way it helps people with smaller resolutions skip past the top of the page and have the image at the top. I edited the displayimage.php file to put in a name anchor, but can't find where to put the target link in the thumbnails page or wherever you find the code for the links to the fullsize image.
You will find the code which create links for thumbnails in theme.php file of the current theme.
The target links for thumbnails are created in the function theme_display_thumbnails() and target links for filmstrip thumbnails are created in the function theme_display_film_strip().
'{LINK_TGT}' => "displayimage.php?album=$aid$cat_link&pos={$thumb['pos']}",