How to edit DVD on Mac including trim, crop, combine DVD clips on Mac

DVD as a format had two qualities at the time that were not available in any other interactive medium: 1. Enough capacity and speed to provide high quality, full motion video and sound, and 2. low cost delivery mechanism provided by consumer products retailers who quickly moved to sell their players for under $200 and eventually for under $50 at retail. In addition, the medium itself was small enough and light enough to mail using general first class postage. Almost over night, this created a new business opportunity and model for business innovators like Netflix to re-invent the home entertainment distribution model. It also opened up the opportunity for business and product information to be inexpensively provided on full motion video through direct mail.
 

However, I found many people want to know how to edit DVD on Mac as below.
 
Q1: How to edit a DVD on Mac?

I have a MacBook. If I get a DVD, pop it in, and want to edit it for content i.e. (make an R-rated film more PG-13) can I use iMovie? Or what would be the best way to do it?

Q2: How can I edit a video on a DVD on my Mac?

I have a ibook G4 and i have the imovie thing but i dont know how to export the footage from the dvd that is made by me to the mac? Does anyone know?

Luckily, a friend of mine recommended me a DVD Editor for Mac which he tried very great. I download the free trial and found it's very easy to use, and can edit options for Mac users to personalize the ripped DVD movies. You can easily trim any clips of DVD movies, crop the redundant edges and add some effects. Then I bought it without any hesitating. If you have the same problem with me, maybe you can try it. Learn the details about how to edit DVD on Mac! You also can convert your DVD to FCP, or DVD to FCE for editing. Hope to help you. More about DVD to iMovie, Sony DVD to iMovie.