If you've got the vob files but nothing else then get
Ifoedit (free download) & this will create the ifo/bup files for you.
Typically this is what you should have in the Video_ts folder:-
VIDEO_TS.BUP
VIDEO_TS.IFO
VIDEO_TS.VOB
VTS_01_0.BUP
VTS_01_0.IFO
VTS_01_1.VOB
VTS_01_2.VOB
VTS_01_3.VOB
VTS_01_4.VOB