check out videohelp.com, they are a great resource, its mainly PC-based, but they have sections for Mac users.
you can backup the DVD's with the program "DVDBackup", I use it all the time, and it works great, havnt had 1 single problem with it. takes about an hour (on 1ghz G4) to rip the DVD.
you will more than likely need a dual-layer burner to burn the images, sence I believe the famly guy DVD's are dual-layer. or another option is to compress the DVD. you can use a program called "DVD2OneX", there is a small shareware-fee you have to pay for it to use it fully but the program works great, and its worth the price.
once you have the compressed DVD, You can use Toast 6 to burn the DVD.
that process works great for me 🙂