Before you spring for the fullframe version, it might be worth considering Douglas Pratt's comparison of the widescreen and fullframe LDs of BTTF2, originally published in The LaserDisc Newsletter:
Re: James Cameron's supposed "preference" for 4:3 versions of his Super35 films.
This is an internet urban legend perpetuated by careless commentators like some of those cited by Mr. Patterson above. Most of the people who parrot this canard have never even seen the single statement by...