He’s best known, of course, for the Charlie Brown animated specials — he directed all the early specials as well as three feature films. A Charlie Brown Christmas will be coming out in a special edition DVD later this year (a new edition of It’s the Great Pumpkin, Charlie Brown just came out), but my favourite is actually the second special, Charlie Brown’s All-Stars, which doesn’t get shown a lot because it’s not tied to a holiday; it compiles many of the best baseball jokes from the strip and ties them together with a really solid story that makes you believe that there’s a real emotional connection between Charlie Brown and the other kids, without selling out the strip’s basic pessimism. (The trick of the specials was always to have relatively “happy” endings even though the format of the strip required most of the stories to end sadly; some specials managed that better than others, but the early ones, like Charlie Brown Christmas, make the happy endings work.) Not only that: when it was decided that Snoopy shouldn’t talk or think out loud in the animated version, Melendez came up with Snoopy’s non-verbal squeaks and squawks, and provided Snoopy’s voice for the next 40 years.
Before Melendez became a director, he was a superb animator. You’ve seen his work most often in Warner Brothers cartoons; he was at Warners through most of the ’40s (except for a stint in the army), working for three directors: Bob Clampett, then Arthur Davis, and then Bob McKimson. His animation was the perfect blend of Disney-style fluid acting and movement with Warner Brothers wackiness.
Here’s a Davis-directed Daffy Duck cartoon, identifying which scenes Melendez animated — his first scene starts at about 1:58. (Thanks to “cartoonzrule” for posting this. And cartoons do rule.)