You'll want to install X (I think it's XFree86 package for RH9, newer distributions use Xorg commonly) and a desktop environment such as
- KDE
- Gnome
- XFCE
So, if you have the install discs, locate there XFree86 package(s) and install them, and after that the desktop packages; gnome and kde have quite a lot of packages to install, xfce a few less; anyway, all the needed rpms are on the disks, you just might need to install them in a specific order to satisfy dependencies (or alternatively copy all the packages you need to your HD and then set rpm to install them all in once).
And after the installation is finished, use
to get into graphical mode if it doesn't pop up right away, and edit your
/etc/inittab file if you want the graphical login screen to be automatically launched at boot: in the file change the
initdefault from 3 to 5, if it's not already set.