I love the 1994 version of Black Beauty. I also enjoyed Hidalgo, Secretariat, Seabiscuit, and quite a few others. War Horse was alright, it could have been better (if they had stuck a little closer to the book, it probably would have worked better)
I hated the 1970s version of Black Beauty (it is so different from the book, it is really Black Beauty in name only), Running Free (cliched, inaccurate, and the horse changes from shot to shot). Most horse movies to me are just rather dull, and cliched.