So...
the video files that I extract from my TPM dvd do not contain the subtitles needed
Are you trying to say that you have ripped only the VIDEO stream from the DVD ? What do you have on your harddisk, a m2v file or a directory named VIDEO_TS containing ifo, bup and vob files ?
Beacause if you have ripped only the video or in general ripped the DVD in IFO mode, there is the problem.
VOB files contain 3 types of streams - video, audio and subpicture (used for subtitles and menu buttons) streams. To correctly use SubRip you must rip the DVD in DVDDecrypter's FILE MODE, then load the main movie's ifo file in SubRip, then select the correct subpicture stream (I guess you want to use English - forced) and you can start, it's really easy.
If this doesn't help please write exactly what you are doing (NOT what you WANT to do) and what error occurs (if any).