What's the best way for adding subtitles to a mpeg file???

-> With VobSub you get a *.sub and a *.idx from your IFO file.
-> With Subrip, you get a *.txt or a *.srt file from your IFO/VOB.

Wich file can be added as a subtitle to your Mpeg and using wich program???

...need some help.......
Thx.
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