How to make a Backup

We have installed ViciDial along with Asterisk on Slackware 10.2 and would like to take a backup of the entire installation and configuration. What is the best way to go about it?
Which files do we backup? The machine does not have a DVD burner so we have save everything on a CD drive.
Any suggestions would be greatly appreciated. Thanks
Which files do we backup? The machine does not have a DVD burner so we have save everything on a CD drive.
Any suggestions would be greatly appreciated. Thanks