I don't like First Contact
in the slightest. Star Trek is an adventure show, but it stepped on major themes in Star Trek II, Moby Dick and all. It wasn't like this for Picard by the end of Descent, Part II. They covered this material in the show. That's my first complaint.
The second is that Zephrame Cochrane is told exactly who he will become. He's no longer living his life as if he has no idea of the outcome. It changes the universe of Star Trek and takes away from the greatness of Cochrane. Imagine if I, in the 21st Century, traveled back in time and told George Washington he must cross the Delaware. Tell him everything about the United States. It's crazy.
Star Trek: Insurrection
is my favorite and I have talked about it ad nauseum on this board.