To change the gnome XTerm background color (and text color) follow the instructions below.

First of all install the gconf-editor tool

sudo apt-get install gconf-editor

Start the gconf-editor tool and go to apps -> gnome-terminal -> profiles -> Default and change the foreground_color to #FFFFFFFFDDDD  and the background_color to #000000000000 .

Go to an open XTerm window and open the Edit menu and select Profile Preferences. On the colors tab uncheck “Use colors from system theme”.

That’s all; your XTerm terminals now have a black background with a white text color.