Once you've reinstalled RH make sure you turn off services you don't need, and then keep current with updates & patches on the services you do run. RH has an up2date GUI tool that will check for updates & download them for you. Roberto would tell you to switch to Debian and use their cool apt-get tool to stay current (right Roberto?
. If you stick with RH and need a non-gui tool, I've recently written a Tcl script that I can run out of cron to fetch security updates and them spam myself once they've been downloaded so I can know to install them (or at least check them out). If you'd like a copy let me know. (I need to get around to putting it up on my personal website one of these days...)