Help for new italian bluray consumer

Hello, i have a bluray palyer about 10 days and i like to do backup of my movies.
I want to take only the main movie with only italian language and italian subtitles for copy it on a 25 gb disc.
How i can do it? I have see dvdfab,but i see that when i use it for rip only the movie i must transform the audio dts or other hd audio in AC3 mode, i not want it, i want to have the original quality audio and reduce the quality video (you remember dvdshrink ? )
Please tell me how i can do this and what programm i can use for have good result.
P.S. i not want MKV. file, i want a bluray disc in my 25 gb space.