There is nothing special to do. Back up your data, set the BIOS to boot from the DVD, insert the DVD and reboot. The installation is very similar to RH9. Just select your existing linux partitions and reformat them and install.
One thing you might consider...If you have your /home directory on a separate partition, you can leave the data in it untouched, but continue using it as your /home directory. It saves some time that way. Your new FC2 install will still be able to access your files in /home and the personal configuration files will still be there for programs.