WinX DVD Ripper is being offered free again.
I've used this for a little while and it seems to do a pretty good job of backing up DVDs.
No email address or anything required. Just hit the 'Get Register Code' button on the page, download the program, install it, paste in the license code and you're away.
A little tip as well - if you have two (or more) DVD drives in your PC, you can create extra Windows users, register the software for each user, and then rip multiple DVDs at the same time :)
(power user edit) - AA-VIEBEBJM-CMZPLX - everyone has the same code, no signup required.
Darn. Just bought it last week — albeit with a significant academic discount!