I was torn between
Batman '66 and
The Dark Knight. Certainly TDK is the most brilliant and powerful Batman movie ever made. But the question was about my favorite, i.e. the one I derive the most enjoyment from -- and that specific phrasing, "favorite Batman" rather than "favorite Batman production," makes me feel I had to go with which version of the
character brought me the most enjoyment. While TDK is an awesome movie, Christian Bale will never be my favorite Batman. Of the actors who played him in live action, I have to go with Adam West as the one I've found most enjoyable, and his show (and the associated movie) as the live-action interpretation I've been most satisfied by on the whole. (If you consider the Nolan trilogy as a whole, it has a lot more weaknesses than TDK does by itself.)