burninfool gave you the answer. PAL vs NTSC has nothing to do with this at all.
You can not remove the widescreen format without re-authroing the whole dvd.
I suggest you live with it.
Personally, I prefer widescreen over 4:3. Movies in 4:3 have the outside edges cut off and the remaining frame expanded to fit your TV screen. In simple terms: you loose nearly 1/3 of the visible screen.
Watch the movie the way the director intended: widescreen.
try watching a few of Clint Eastwood's "Spaghetti Westerns" there are lots of shots where there are only 2 people in a room (bar room), each on opposite sides of the room. Nothing in the middle. Cutting it to fit 4:3 would be interesting...
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