Having mentioned I enjoyed the Let It Be DVD, Andy Capper recommended Gimme Some Truth which documents the recording of John Lennon's Imagine. Almost any music documentary I find watchable, and the highlight of this one for me is the added extra of an uncut 40 minute interview with a relaxed John and Yoko on the topic of pop music, sex, and love. Both are remarkably articulate, and it is a poignant reminder of what Lennon obviously loved so much about her.
P.S. next instalment of the Judith Howard interview coming soon (much frantic transcribing...).