If you rip the dvd in LMCE it creates a filename.dvd file and also a filename.id3. The .dvd is an iso image. The .id3 contains the meta data, chapter names, actors, genres, cover art, etc. (it gets this automatically).
If you have already ripped dvd's, just rename them to .dvd and lmce will play them. Most Linux dvd rippers don't look up the dvd's cover art and meta data, so you might not have this. In this case, go into lmce's admin panel choose Files & media, cover art. It will scan amazon using the filenames as keywords, adn then give you matrix to pick the cover art that matches each dvd, and it will automatically pull the actors/genres/etc. so it catalogs them.