I don't mean to bog you down with semantics, but I'm guessing that you're referring to "shading", right? Where the window "slides up" into the titlebar, leaving only the titlebar on the desktop?
I don't know for sure whether or not it will help, but you can try this:
http://fedoranews.org/dowen/tips/tip-007.shtml
I hope it helps. I can't help but think that whatever your specific setup/GNOME version is, the solution should be fairly similar to the one suggested on the above page.
Good luck!
