i tried to install RealPlayer(as root). So i typed:
# rpm -ivh compat-libstdc++-33-3.2.3-47.fc4.i386.rpm

I got this error:
warning: compat-libstdc++-33-3.2.3-47.fc4.i386.rpm: Header V3 DSA signature: NOKEY, key ID 4f2a6fd2
Preparing... ########################################### [100%]
1:compat-libstdc++-33 ########################################### [100%]


Then, i entered:
# rpm -ivh RealPlayer10GOLD.rpm

I got this reply:
Preparing... ########################################### [100%]
1:RealPlayer ########################################### [100%]


I typed:
# rm *.rpm

I got this:
rm: remove regular file `compat-libstdc++-33-3.2.3-47.fc4.i386.rpm'? y
rm: remove regular file `RealPlayer10GOLD.rpm'? y


Lastly, I entered:
# yum remove HelixPlayer

I got this error:
Config Error: Error accessing file for config file:///etc/yum.conf

What should i do?

*btw, i followed the instruction in stanton-finley.net/fedora_core_4_installation_notes.html#Real

It sounds like it's having problems accessing your yum config file. What does give you?