.iso - Disk Images
If the ISO file has been damaged File Juicer may extract files from it, but this should happen rarely.
If you ended up on this page you may be interested in How to enable more formats in Disk Utility - which also refer to the "hdiutil" utility in the Terminal.
To create an ISO disk image "mymix.iso" for a folder "MyMix" you can use the Terminal application and type this command:
hdiutil makehybrid -o ~/Desktop/mymix.iso ~/Desktop/MyMixYou can burn the .ISO to a CD with Disk Utility.
Wikipedia article: ISO 9960