Actually, logging into Gnome as root is no problem. Just don't try to use any of the Mandrake KDE specific programs. As for Mandrake not wanting people to log in as root, that's pretty lame. I can do the same damage under a users id with su. I don't believe this is a feature that Mandrake wants (imho). For me it's just a lot easier to log in as root and make my changes instead of typing the root password 20 times in a users session (OK, maybe not 20 times, but you get my point).
Oh, and to clarify my point. It's not the red background I care about, its actually using the desktop within KDE as root. Just thought I would ad that since some people think I am talking about the red background for some reason.