How do you open CDI, EXT,MPEGAV,PICTURES,SEGMENT and VCD files?

OK, so we got a CD with videos downloaded on them from a foreign country by the way ( if that will help in any way). We tried opening them with real player and media player, but they still wouldn't open..so there is a dilemma here..how do we open the files?? There are folders that read CDI, EXT,MPEGAV,PICTURES,SEGMENT and VCD ...so how do we open them to get the videos to play?oh ..and ...you've probably figured this out by now..but I'm computer illiterate....