FairUse Wizard can use an ISO image of a DVD that’s on the hard drive; but not DVD folders (ie those labelled ‘VIDEO_TS’ and containing .IFO, .BUP, and .VOB files).
You can quickly convert the VIDEO_TS folder and its content to an ISO image using ImgBurn. Just select the ‘output’ to ‘image’, select ‘Build’ mode, load the VIDEO_TS and AUDIO_TS folders into the window and press the big icon ‘folder-to-ISO’ button.
Once you have the ISO image, then you can open it in FU.
BTW another advantage of FU is that the recent versions have multicore processor support.