How can I split a DVD9 with two 'apparent' equal titles 5 Gb large?



Hi. I’m starting doing something very new, for me.
My aim id to split exactly a DVD9 in two DVD5; the first DVD which will contain part of the movie and all extras, the 2nd which will contain only the remaining part of the movie.
I have found that an old version of DVD Shrink (2.3) includes the ‘starty/snd’ button, and followinf the guide present in I thought that splitting ripped DVD9 —> 2* DVD would be very easy.

Yesterday, when I was learning to use this procedure, I found a very strange issue. I put my DVD of ‘Daredevil’ and all programs I used (DVD Shrink 3.2, 2.3, DVD Decrypter, ReJig in IFO mode) said that the movie (1:39:10) was on ‘Title 1’ and ‘Title 3’ (even if DVD Decrypter, in IFO mode which I use if I need to rip the moviie only, enlighted only Title 1).
What happens is that DVD decrypter in ‘File mode’ sees that the DVD contains 5980 MB of files, but if I go to DVD Shrink, it puts under’main movie’ both Title 1 and Title 3 (both of about 5 Gb). That is, under ‘main movie’ I see (Title 1 + 3) both about 5 Gb large and a movie over 3h long!
Please note that the audio streams which exist cannot be distinguished; I see an English AC3 trace, and Italian [my native language] AC3 trace, an Itaian DTS trace and a trace containing ‘director comments’.

What should I do? Ignore Title 3 and back up the whole titles presend on the DVD excluding title3 or what?
I wouldn’t have an un-readable output, and I’m sure the DVD cannot contain 10 Gb so the ‘title 1 and 3’ seem to be he same (or, maybe, the same movie with a different type - same language but different content - of dubbing).
Thanks for your support.