What program do i need to open these file types?
I've tried opening them with mplayer but it doesn't do anything...
IFO files contain the formatting information of the VOB files, which tells the DVD player exactly how the DVD should be played (eg. aspect ratio, subtitles, languages, menus ...). BUP files are backups for IFO files, which are needed if the IFO files gets corrupted. If you rip the DVD without IFO files, then the VOB files may not play correctly, or may not even play at all. Similarly for conversion, IFO files are essential since video converters like FlasKMPEG (which supports IFO parsing) will need them if you want to encode videos, or fix multi-angle ripping problems.
Apparently, these are simply formatting-info files with no actual a/v content.
You're missing yourself a .vob
suspected as much but had to check just in case... thanks for reply!