Copy DVD or CD on Mac Using Disk Utility

Select disk utility (Finder> Go> Disk Utility or shift key, command key and 'U')
File new > select disk image from (disk drive)
Name file, select save location
On image format tab, select cd/dvd master
Encryption none (unless needed)
File will save as cdr file
Once file has been created this can be selected and using 'burn' tab cab be used to burn dvd/cd
File can be saved on hard drive for further copies or deleted if no longer required.

You may find it easier to watch the video rather than follow list.

Or click on the link below for an in depth tutorial.

http://youtu.be/xDkCsVlkkG8