Hello pod777, welcome to LQ
Slimserver is a great program, I use it all the time. RPM files are basically archives. To install from an rpm, just find the RPM, double-click it, and enter your root password when prompted. You will see its progress as it installs.
Yum is a neat program that will search internet repositories for RPMs, download the ones you want, and install them for you. There is a good Yum tutorial here:
http://www.linuxquestions.org/linux/...l_applications
You can probably find slimserver with yum, but I haven't looked
