I think you misunderstood me. Popcorn (better link provided this time!) copies and compresses your DVD's, not Toast. It just happens that Popcorn is provided by Roxio, the same people that brought you Toast, and they're offering a discount if you already have Toast.
If you just want to backup DVD's check out MacTheRipper, a freebie app to backup your DVD's onto your hard drive. DVD2One/Popcorn is needed to compress the movies, so then can be burnt onto a single 4.7GB DVD discs.
I second the suggestion for MacTheRipper to rip the DVD - great, free product.
I use DVDRemaster to recompress it and have been happy with that product.
Once ripped/recompressed (often not necessary with MacTheRipper's "feature only" option which only rips the movie itself), I use Toast 6.
My daughter has a lot of Disney DVDs, and, having lost a ton of them once on a flight and becoming painfully aware of how hard/impossible they are to replace, I started copying all of them and only letting her use the copies. So far, it's been a great idea - and the feature-only DVDs play as son as they're inserted - no more wading through all the trailers, menu options, etc.
I just went thru alot of these programs and was looking for a program with a simple interface. Also I wanted a single click format. I use FastDvdCopy and it does a Great Job.