Wierd VMC Subtitles Issue

I just converted my Futurama DVD collection to 75 individual DVD folders. I re-muxed them all to have 2 audio tracks (5.1dolby and 2.0 commentary) and no sub tracks, with no dvd menus. I used the same method to do them all. VLC & powerdvd see no subtitles at all. I added the folders to my VMC library, and all the episodes show up under my DVD library. However, Vista Media Center has subtitles on some of these episodes, and they are better than the original subtitles from the DVD. They will not go away, and I cannot get them to come on for some of the episodes.

Anyone know where these are coming from, and how to control them?