ilovewaterslides said:
1) Is the Mondo a theatrical version or an extended one?
2) What is the bitrate of the audio tracks on the 98 DVD?

Neither. There are three versions now:

a) US Theatrical version
b) Italian Theatrical version
c) US Extended Version

The US Extended Version follows the Italian version for most part, however, it uses the US Theatrical version edit of the torture scene as well as of some shots at the end. Here is a comparison between the US Extended and the Italian version: http://www.movie-censorship.com/report.php?ID=624419

2) The AC3 bitrate is 192 kbps 2.0 mono. That's why I am using the LD PCM audio instead (though it is more severely cut).