@hullap: for once,remove qt and all its dependencies ,remember if u have amarock and other kde things still remaining in ur system,they all are purged out for the benefit of Gnome.u can later install amarok(exaile for gnome) or k3b(brasero for gnome):
Code:
sudo apt-get remove --purge libqt3-mt libqt3-mt-dev
then open nautilus file browser,press CTRL+H to enable hidden files to see.
now remove any dir's which is kde/qt related.that's all what I can think now.
now open theme manager(appearance>theme) select "clearlooks" theme.
now,select customize>"colors" select the color u want for the body of the apps.
here is a screenshot from my debian:change the background color to the one u want.

Hope this solves.
if this too fails,u may have to re-install:
Code:
sudo apt-get install gtk2-engines gtk2-engines-ubuntulooks gtk2-engines-pixbuf gnome-themes --reinstall
now,run gconf-cleaner.get gconf-cleaner from here:
http://ubuntu.org.ua/getdeb/gc/gconf...tdeb1_i386.deb
it will clean out obsolete gconf entries to make clean.