Looks like you don't have KDE installed or at least the libraries it needs to run.
KDE should be on your install CDs. If you have HD space just install KDE. You can then run all KDE apps even if you don't use KDE as your desktop enviro.
You can also use yum. Look at
You need to do something like
#yum update
then
#yum install kplayer
You may have to install KDE first or at least KDE libraries.
http://kplayer.sourceforge.net/
See if you can locate the .rpm, it will be easier for you.
http://rpm.livna.org/fedora/2/i386/RPMS.stable/
In short your going to need some of KDE installed.
Kplayer is a very nice front to mplayer.
edit:
http://rpm.livna.org/fedora/3/i386/RPMS.stable/