i am assuming you are using Gnome
are you using KDE4 ,lxde, xfce, e17, or some other desktop
Gnome is default so file-roller should be the default auto option for double clicking on it
or r-click and select "open with fileroller"
also fedora 14 is a DEAD version
there currently is NO support
There will NEVER be any updates ,nor any security fixes - it is Past it's END OF LIFE
please stay current if you are going to use fedora and install fedora 16 then in about 3 months fedora 17