Not on the DVD I have.
BTTF writer and producer Bob Gale has stated on more than one occasion that the DVD release of the first film is exactly the same as the theatrical release. In fact, he made that statement just the other day in a live chat:
This includes removing the “To Be Continued” graphic at the end of the first film, which did not appear in the theatrical release but was added for the home video version. (There are intense arguments about this similar to those about the “Episode IV” line at the beginning of Star Wars.)
[hijack]Speaking of the BACK TO THE FUTURE dvd set, I read that some gay groups were upset at a homophobic scene in the deleted scenes. Does anybody know what this was about and whether it was a legitimate reason to gripe or a get over yourself thing?[/hijack]
It was a throw-away joke. Marty is having reservations about the plan for night of the dance. The dialogue with Doc Brown went something like this:
“I don’t feel right, you know, hitting on my own mom.”
“Who said anything about hitting her? You’re just going to take a few liberties with her. ;)”
“Yeah, see, that’s what I mean. I mean, feeling up my own mom. This is the kind of thing that could really screw me up. What if I wind up, I don’t know, gay?”
“Why shouldn’t you be happy?”
“Uh… yeah. I gotta go.”
Oh good Lord, was that all? Some people really need to get a life.