The situation: I was making some installation CDs of RHEL 5 from downloaded .iso files on my Mac workstation for our servers. There are a few different ways to burn CDs on the Mac, so my first efforts made readable file copies but not bootable CDs.
The solution: use the Disk Utility (under Applications/Utility). Drag your .iso file into the DU's left-hand navigation area and then click the (now enabled) "burn" icon on the top of the DU.
Here's your 4th of July bonus: http://hypem.com/search/ray%20charles/1/