Like basically everyone alive at the time, I loved the movie and couldn't resist the urge to play the game. Thankfully but 1989 it was possible to get games at Blockbuster video so you would only waste $2 if a game was a piece of crap....and this game was definitely that.
At the time I was unaware of the fact that LJN games, especially the ones based on movies, were pretty much terrible across the board. Later in life, whenever I would see that rainbow logo on a box I wouldn't even pay any attention to what the game was about because the LJN symbol is the opposite of a symbol of quality.
The gameplay basically borrows from a bunch of other games in existence and then tries to have stages that are loosely based on the movie. Most of the game is done skating and walking down the street collecting clocks that if you get enough of them, will restore your family members in the picture. This part of the game functions almost exactly like Paperboy. Later their are stages where you have to confront Biff and resist the "kisses" from your Mom, Lorraine.
one of the silliest stages of the game involves Marty being on stage where you need to "catch" the notes in order to have your parents kiss on the dance floor. After that you go to the final stage where you will dodge lightning to arrive at the "finish line" to send you back to 1985... just like in the film but stupid and with a soundtrack loop of Power of Love that is so short the audio in the game will cause you to lose your mind.
This game was awful across the board especially when you consider how late it was released in the NES console's existence. The Super Nintendo and Sega Genesis were about a year from introduction and other Nintendo games were much better in terms of graphics and sound. The makers of the film were not allowed any input into the game and when they did finally see it they called it "one of the worst video games ever made" and encouraged their own fans to not purchase the game.
This was one of the most disappointing games of my childhood and was a real lesson to young me about the dangers that is LJN. I don't recommend anyone play it but if you do enjoy torturing yourself the ROM is available HERE