For your needs,
MacTheRipper is perfect, just like pjrobertson said before! It's also free.
However, MacTheRipper is just a ripping tool. It copies the DVD data (.vob, .vts, etc.) from your copy-protected DVD to your harddrive!
What it can't do is shrink the DVD data, to make it fit on a single 4.3GB DVD, or even burn it!
If you need to shrink the DVD data, you can use
DVD2One! It's trial software and costs about $40.
In order to burn the shrunken DVD data, you can use any burning app.
I use
Roxio Toast by default. In my opinion, it's the best burning tool for OS X, but it's also kinda expensive ($79.99)!
Toast
can shrink your DVD data while burning it, so you won't need DVD2One!
You might also want to check out
Disco! It's a cheaper alternative ($19.95) to Toast and can do about the same stuff. Also, it's pure eye-candy!
Roxio Popcorn can copy (ONLY UNPROTECTED DVDs), shrink and burn the data, but apart from encoding, compressing and basic editing of videos, you can't use it for much more!
Sure, it's cheaper ($39.99) than its big brother Toast, but it's also a stripped version!
It's not qualified for other stuff (data-, music-, bootable-CDs/DVDs, etc.)!
Method 1: MacTheRipper + DVD2One + Disco = $59.99 (GOOD)
Method 2: MacTheRipper + Roxio Toast = $79.99 (BEST, MOST REWARDING)
Method 3: MacTheRipper + Roxio Popcorn = $39.99 (CHEAPEST)