you also might want to read some of the manuals that are around
like " The Red hat enterprise Linux 5 Bible "
but 5.0 is mighty OLD the current in the older 5 series is 5.8 ( soon to be 5.9)
or read the red hat documentation
-- the docs for the older 5 are in the middle of the page
the current book for the current OS RHEL6.3