The animated version of TLOTR was something of a disappointment for me, especially since it stops more or less abruptly in the middle of the tale. Apparently they were planning on finishing it up but they never got funding for the continuation of the project. I think the humans were filmed with live actors and then the film was painted over for "animation." (Or "deanimation" maybe.)

There was also an animated version of "The Hobbit" but it was rather childish and full of irritating songs, if memory serves.