When watching "100 Years of Warner Bros.", the first thing to keep in mind is that it's a documentary about Warner Bros.--made by Warner Bros. As such, there is little impartially which leads to a bit of a capped ceiling for the project. But as long as you can look past that self-promotion angle, there is a lot here that can be enjoyed from a film-lover's perspective.
The first episode--about the Warner brothers themselves, the creation of the studio, and the old "studio system" of Hollywood--is probably the best, as it is the closest to new information a viewer is going to get here.
The next three parts are all essentially hour-long clip shows talking about WB's media properties. Fortunately, it isn't nearly as bad as that statement may sound because, quite frankly, WB has perhaps the most impressive library of any studio! Even in the three hours after the introductory ground-laying, director Leslie Iwerks barely scratches the surface on WB's famous endeavors.
Overall, I give "100 Years of Warner Bros." an 8/10 score. It is nostalgic and entertaining for celluloid lovers even if its insular, self-aggrandizing nature prevents it from being anything more.
