I'm not entirely sure about this one, I've de-interlaced quite a few music videos from vobs & they've turned out great - yet I've used multiple software's including Topaz Video AI.
Topaz is cool program, but not much friendly with VOB. For good results you must have original DVD file from DVD without transcoding. Because any downloaded file (what was supposedly converted/compressed) have those image issues, but if you copy vob from dvd, then it's okay.