Is there a length of time in which a movie is not a movie? Is there point where the movie is to long to be a movie? I am looking for some kind of time table in which movies are classified.
It's somewhat a matter of opinion. However, the Academy of Motion Picture Arts and Sciences defines a short movie as having a running time of 40 minutes or less (pdf).
By their definition a "full" feature length movie has to be more than 40 minutes.
I am not aware of any upper limit, there are movies such as Andy Warhol's Empire (1965) which is over 8 hours long and was shown in movie theaters. If that seems too much like an art installation rather than a feature film, there are a number of mainstream movies that are far longer than most made today: