Yes. Massive Attacks Mezzanine is, indeed, a great choice.
Then, I?d recommend this Ninja Tune Sampler, its even better, don?t remember its name, difficult to get, I think the name is Trip Hop and Slow Jazz... recorded in 93?.
Another good choice is "Come" by Prince.
An unusual, but great choice would be a rocking Blues album, one with full fledged band, John Lee Hooker, or what about Dr. John. Marvin Gaye?s a good pick as well.
Jazz yes, but no Miles Davis, maybe sth. like John Coltrane?s "Ballads", this is very slow and romatic though, more for the cigarette after...
And finally "The Great Gig In The Sky" song on dark Side of the Moon by Floyd.
Sorry I didn?t pick only one... my nights are long
... my pick out of those I mentioned would be the Ninja Tune album, though.