VOB file support was added in CS4 with the 4.1 update, however non-standard VOB files remain problematic.
You cannot easily edit VOB files from a DVD with Premiere Pro - You need to rip the files to your hard drive and then convert them to DV AVI Type 2 format before editing them. See www.VideoHelp.com for complete instructions and for many utilities to achieve your goal. They also host a forum for people to discuss the same thing over and over again.
Some people have reported success renaming the VOB files to MPG and then editing them in Premiere Pro, however you are likely to experience problems. You may be able to adjust the "File options" for deinterlace and flicker removal options. Or make it easy on yourself and convert the files to an editable format like DV AVI, it just works. See also: FAQ:Why is there no audio in my imported MPEG file?
Another way to deal with .VOB files if you rename them to .MPG is to import them into Adobe After Effects 7 (earlier versions may not work) and export to Microsoft DV AVI (Type2) from there. It isn't fast, but it works.
If you absolutely must edit MPEG2 videos in Premiere Pro 1.x there is a plugin available for Premiere Pro 1.x at http://www.mainconcept.com
A forum member has recommended the free utility MPEG Streamclip for converting the files.
Hook your standalone dvd-player up to a camera with video(analog)-in and capture with firewire to the pc.
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