If it's not copy protected I believe mpeg streamclip (it's free - www.squared5.com, and you have to use the "www") will let you set an in and and out point in a VOB file and export to format of choice (as long as you have Compressor or the Quicktime mpeg2 component).
Brook _______________________________________________________ Brook Hinton film/video/audio art www.brookhinton.com studio vlog/blog: www.brookhinton.com/temporalab