First off RHEL 5.4 is VERY old .The current in the old 5 series is RHEL 5.8 ( 5.9 is in testing)
And the current
release is RHEL 6.3
Also RHEL is not really a free operating system.
You MUST buy a "support contract / License"
for the desktop license it is from $49 to $299 PER YEAR
basically if you do not buy the license you do not install software
Install one of the FREE rebuilds
-- for the rather old 5
CentOS5.8 -- might NOT install on new hardware ( to old )
ScientificLinux 5.8 -- might NOT install on new hardware ( to old )
--- the current --
for installing by a usb thumb