What I liked:

• the time travel scenes themselves, of course, although the requirement of zooming into an unknown area at 88 miles per hour would scare me enough never to attempt it, but that’s me. Later on, thanks to a trip to the future, the car flies. Shades of Chitty Chitty Bang Bang.
• Biff. When not portraying towering bullies, Thomas F. Wilson is a stand-up comic. He also plays the tuba, so in reality, he has more than tasted the nerd’s life. And better, he’s all but unrecognizable as paunchy, middle-aged Biff, yet pulls off both pushy and wimpy Biff equally well. He’s so menacing as young Biff that I just don’t buy Marty even sqaring off against him, let alone besting him in the long chase sequence through town.

What I didn't like:

• Zemeckis’ baffling depiction of women. I’ve yet to see a Zemeckis film where women were anything other than weak, fickle, flaky, lacking in any real character, or in the case of Marty’s girlfriend (played by TWO different actresses in the trilogy, but did we notice?), practically non-existent. She spent almost all of the next two films unconscious, fergawdssake. As for the various incarnations of Marty’s mother (and great-something grandmother in Part III), I can think of fewer women more shallow in modern cinema.
• Not much need to comment on Crispin Glover’s ultimate spaz George McFly, who twitches uncontrollably like a victim of advanced Parkinson’s (a level which, one hopes, Mr. Fox himself never reaches). I’ve seen severe cases of nerdism and geekiness, and Glover is just too much even in comparison.
• Throughout the film George is portayed as a frustrated writer, only to be urged to follow his dreams by his own future son. Apparently he does, for the present that Marty returns to is changed; his family now seems quite functional, with Sis inundated with boyfriends, Bro working in the corporate world (and on a Saturday, and still living at home, for some reason), and Mom and Dad healthy, successful and frisky. This is all great, but successful at what? They receive a package that contains what Mom describes as George’s first novel. His first?? What’s he been writing before then? And why is Big Brother going to work on a Saturday in a business suit? So when Marty returns early to save Doc from the Libyan terrorists, his other self, whom he watches escaping in the DeLorean, had been living with that great family all this time. Sure, and future Marty just takes over, the bastard.