I definitely recommend MacTheRipper as well. Although you can still download MTR 2.6.6 for free, the newer beta versions do require a contribution (gift). I highly recommend joining the MTR forum and supporting the developer of MTR as DVD rippers for Mac are becoming quite scarce! Keep in mind that MacTheRipper is just that, a ripper. It doesn't compress or burn movie files and it's not designed to rip non commercial DVD's (these discs don't require ripping).
http://www.ripdifferent.com/
Oddly enough I've never used Disk Utility to burn a movie DVD but you might want to give it a shot.
Duplicating a CD or DVD:
You can use Disk Utility to quickly copy many types of CDs and DVDs. In the steps below, you'll create a disk image of the disc, and then use that image to burn copies.
Disk Utility cannot create usable copies of discs that use an incompatible format or are copy protected. These include most movie DVDs and audio CDs and some software and data discs.
Insert the CD or DVD disc in your computer's optical drive and select it in the list of disks and volumes.
Choose File > New > "Disk Image from [name of disc]."
Type a name for the disk image.
Choose "compressed" or "read-only" from the Image Format pop-up menu.
Choose "compressed" to create a smaller disk image, and choose "read-only" to create a disk image that's quicker to create and open.
Click Save.
After Disk Utility creates the disk image, eject the original CD or DVD.
Select the disk image in the list of disks and volumes, and choose Images > Burn.
When the Burn Disc dialog appears, insert a blank CD or DVD, and then click Burn.
You can continue using the disk image to create as many duplicate discs as you need.
Here's a link for a free burner for Mac. I can't vouch for it but it is highly rated.
http://www.versiontracker.com/dyn/moreinfo/macosx/28245
