Decades ago I made a tape from the movies I had recorded featuring songs I loved. E.g. Oz and Over the Rainbow, Delightful to be Married from The Great Ziegfeld, etc... (many of my friends felt I was really 'out-there' since they were creating Van Halen compilations and I was doing this!).
But I'm not sure one could make such a compilation from noir films since the songs are rarely featured in the film; I.e. they are background music and therefore after a few seconds there would be dialog over the music. E.g. Laura. So it might work better to create a compilation from recordings made by singers that do the songs from those films; e.g. Laura - The Nat King Cole version is fantastic.
As for Elevator to the Gallows: The soundtrack was recorded by Miles Davis and his band while watching the film. The complete soundtrack is available on CD.
Thanks! Somehow, I find that I mostly enjoy this music when I watch the films. I'm not sure if I would ever go to the trouble of actually buying the soundtracks and/or making a CD compilation. For some reason, I feel that the music goes hand in hand with the movies, that I might not enjoy the music as much if I hear it without the movie, if that makes any sense (probably not..ha ha). But hey, thanks for the information!