How to add subtitles, cut part of a movie and create a DVD
 

I have a movie in xvid format with no subtitles.
I created a subtitles file for it.

I now want to add the subtitles to the movie and create a DVD of only part of the movie.

To ensure synchronization of the movie and the subs it seems the best way is first to add the subs then edit the movie.

DeVeDe is great in converting the movie from xvid to vob, adding the subs, and creating the DVD in one step, but I can't find a way to cut the unwanted portions.

In DeVeDe I found I can add the subtitles and convert the movie to mpg, and it will retain the subtitles. I'm looking for a way to cut out parts of the mpg; then I could use DeVeDe to create a DVD from the edited mpg.

What program could I use to edit the mpg file, and how?
Is there a better way (that is, without converting to mpg first)?

I have avidemux2_cli and avidemux2_gtk, mencoder.

I noticed ffmpeg loses the subs when I try to use it for this purpose.