Commercial movies on DVD (if not pirated) are copyright protected and most 'official' software packages (e.g. Nero, Handbrake etc) will not let you rip them. If you want to do this for free, you can use a two step process - something like DVDFab to rip and then Handbrake or Super Media Converter to convert. If you want to pay, you can buy an upgraded version of the likes of DVDFab that will do both steps in one. There are a huge number of options really and half an hour in Google will help you find the best one for your exact circumstances.
Copying (ripping) a DVD is illegal, in fact it's piracy just like if someone took one of your images and put it on their own website.
While it is illegal what you describe isn't the same, putting it on a website is making it available to others wheras transferring a movie you have paid for to your own personal device isn't making it available to anyone else.
Surely it isn't illegal if I'm making a copy of a film I legally own? It's no different to adding music to an iPod or a music library on a PC.
You'll probably find the terms and conditions you clicked through (we all do!) say that you're buying a licence to use, rather than actually owning it. Indeed, Kindle/Amazon have recently remote wiped a womans Kindle reader of all her purchases after closing her account in a dispute.
From T&C's "Kindle Content is licensed, not sold, to you by the Content Provider."
My understanding is that format shifting for personal use is tollerated, if not actually legal.