For an on-the-fly decrypter working on the background, nothing can beat the reigning King AnyDVD/AnyDVDHD. Of course, there is no free lunch here though Slysoft discounts them from time to time.

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If rip-to-HDD and then convert is the way you choose then of course the free DVDFab HD Decrypter is one solution. As per their recent policy, updates to new protection removal to the free version may be delayed upto 30 to 60 days after release to licensed users. May not be a serious issue though.
As an alternative, you may also try MakeMKV -
MakeMKV - Make MKV from Blu-ray and DVD - to first make an mkv and then convert it to mpg or mp4 as you may choose. ( It does not compress but just puts the original in an mkv container)
The salient features of MakeMKV:
Reads DVD and Blu-ray discs
Reads Blu-ray discs protected with latest versions of AACS and BD+
Preserves all video and audio tracks, including HD audio
Preserves chapters information
Preserves all meta-information (track language, audio type)
Fast conversion - converts as fast as your drive can read data.
No additional software is required for conversion or decryption.
Available for Windows, Mac OS X and Linux
Functionality to open DVD discs is free and will always stay free.
All features (including Blu-ray decryption and processing) are free during BETA.
You may choose one that you are happy with after trying both.