Even though it would help growing up with the movie, it doesn't diminish the greatness of the film. I had E.T. t-shirts, memorabilia, board games, Atari games, Halloween costume, so it is easily said that I was into the movie. I was 7 at the time I saw the movie so the fact that I didn't know what the alien looked like yet had me "nervous". Obviously that changed pretty quickly.
There are many reasons that this was the top grossing movie of all time for such a long period. The movie is emotional and funny. It follows a kid who is basically alone and wanting for a "real home" since his dad passed away. He finds what he needs by finding a being that is having the same issues as E.T. "lost" his family by being left behind. It really is a story of growing up.
Henry Thomas did win and was nominated for awards for his performance. For instance, he was nominated for a Golden Globe for Best New Male Star. Drew Barrymore was also great in the film as you could tell she really though E.T. was real.
Plus how can anyone not enjoy some Reese's Pieces.
Easily an A+