The greatest DJ of the 60's - that's a hard question to answer, it all depends upon which market is your point of reference. I'll go back and include a few from earlier years, and various markets:
Tommy "Dr Jive" Smalls - WWRL, NY
Peter Tripp - WMGM, NY
"Jocko" Henderson - WLIB, NY & WHAT - Philly
Willie "The Mayor Of Harlem" Bryant, WHOM, NY
George "Hound Dog" Lorenz - WKBW, Buffalo
"Symphony Sid" Torin - WEZE, Boston
Porky "Platter Pushin' Papa" Chedick, WAMO, Pittsburg
Chuck Dunaway - WRIT, Milwaukee
Al Benson - WGES, Chicago
Herb "Kool Gent" Kent - WBEE, Chicago
Hunter Hancock - KFVD, Los Angeles
Art LeBoe - KGFJ
Dick "Huggie Boy" Hugg - KRKD, Los Angeles
Notice, for the most part, DJ's from the past had a hook in their name - something to push in their quest for popularity. We don't get much of that anymore.
On the subject of DJ's - and motion pictures, something no one has mentioned. The 50s brought us many fine films to highlight and showcase the music of the era and the teen rebellion which scared the pants off of parents. Examples: "The Wild One" (1953) - not so musical, but a classic teen-anger film. Then there was "The Blackboard Jungle" (1955) featuring the song which became a teen anthem and signature for the whole Rock n' Roll movement - Bill Haley/Comets and "Rock Around The Clock." Alan Freed became known nationwide for his 1956 roles in "Rock Around The Clock" and "Rock, Rock, Rock." 1956 brought us even more, with "The Girl Can't Help It," and "Love Me Tender." Sadly to say, another fine DJ, Willie Bryant, emceed two full-length feature films in 1955, "The Rock 'n' Roll Revue" and "The Rhythm & Blues Revue", both of which showcased all-black talent but was geared for a black audience. Few whites knew of their existence, then and today. Watch them if you find them, you won't be disappointed.
Nuff said.