I agree with the comments of Ms J.A.Jacobs about this film bearing little resemblance to its source material, the novel, but it does have a few fine things going for it. Firstly, there is the angelic and totally beautiful Mark Lester, who was 12 years old when he made this film in 1970 (it was released in 1971) and he dominates the film, even though, despite being the main star of it, he's only in the film for the first 26 minutes and is glimpsed again briefly as the end cast plays. He is fascinating to watch and his facial expressions and the look in his eyes when he is watching Black Beauty being born are a joy to behold and are complemented superbly by the music score composed by Lionel Bart and John Cameron.
After Mark leaves the film, it changes atmosphere and tone considerably and seems to be another film entirely, only picking up again towards the end when Black Beauty is rescued from a cruel coal merchant and is reunited with Mark Lester's character, Joe, now a much older young man. The young Mark is then glimpsed briefly as the film ends.
The music score is often very haunting in the first 26 minutes or so and the scenery, set in England, but filmed in Ireland, is beautifully picturesque. Locations in Spain double for the film's other locations, such as India.
As for the DVD, the picture and sound quality are excellent, much better than on the old VHS video release and it's worth every penny of its very reasonable price. Extras include a stills gallery, which include a couple of colour stills from the film's British Front-of-House set (something I am lucky enough to have in my collection) and the original two and a half minute trailer from 1971. Even if you really only want to watch the first half an hour of the film, while Mark Lester is in it, I doubt that you'll be disappointed in this DVD. Go for it!