Yup, Marty was originally going to have a wacky adventure involving a 1950's atomic bomb test site detonation.
And yup, the time machine was originally going to be a refrigerator.
Yup, I'm glad they decided to keep working on the script.
IIRC the getting back to the future via nuke stayed around well into the change of the time machine to a car. There was supposed to be a montage of Marty driving the car back to California from the test-site once he got back to the "present." The nuke thing was dropped because the film-makers thought it was unrealistic (radiation and all) and it'd be too expensive to film so they went with the lightning thing.
But, yeah, the fridge thing wasn't a good idea and it's a good thing they kept working on the script, the DeLorean was made far more of a iconic classic than it would've been thanks to this movie and other changes helped cement the movie as a classic as well.
Ah good, there will be a DVD version. Im not interested in blu ray yet.
There's been a triloigy box-set that's been available for many years now, I believe it's OOP but one could still be found on ebay or probably still on Amazon or in the odd video store. Individual DVD releases have been available for a couple years now.
And now's where I'm going to say something that people are going to jump up my ass for.
I'd kind-of hoped that when they moved the BBTF movies to BD they'd go through the second one and update the special effects. Even on VHS the special effects, model work and such in Part 2 is... not good. It was good in the 90s but doesn't quite hold-up today. Most notably is the scene where the DeLorean "lands" in the Hill Valley alleyway the rear deck of the DeLorean and the exhaust ports are very different on the plastic full-scale light model they used for these "landing" scenes than they are on the "real" thing. When the DeLorean is giving hover-chase to Biff's '46 Ford you can clearly see the real "drive wheels" under the "hovering" DeLorean, these are obviously not supposed to be there. (They're clearly visible on the "corrected" WS DVD version.)
Some of the flying model work in establishing/FX shots in 2015 doesn't hold up well. All of the other SFX work in the other two movies holds up fairly well today -as there's little of it- but the future Hill Valley stuff looks horrible and will look even more horrible on BD. (And are they going back to the film-stock and redoing this or is they simply going to be an "upscaled" DVD?)
Anyway, I've "grown out of" needing Special Features to buy a DVD so it's unlikely I'll buy this set unless there's something on it that'll blow my skirt up.