In RHEL there is gnome-terminal is already added when you right-click on your desktop you will see Open Terminal Option there.
But in Fedora 9/10 and Ubuntu 8.04/8.10 you will have to Start Terminal From system tools or from any different Places.But I am sharing trick that how to add Open Terminal Option in Fedora 9/10 and Ubuntu 8.04/8.10 on right-click.
For Fedora Users :-
Open Terminal (Applications -> System Tools -> Terminal )
then Execute following command
yum -y install nautilus-open-terminal
For Ubuntu Users:-
Open Terminal (Applications -> Accessories -> Terminal)
then execute following command
sudo apt-get install nautilus-open-terminal