Yes 'Roundabout' from Fragile
Steely Dan: 'Black Cow' (Aja)
Miles Davis: 'Blue in Green' Kind of Blue
Weather Report 'Birdland' from Heavy Weather
Pink Floyd: 'Breathe' (DSOM)

There is a theme to the choices I've offered: they all serve as overtures for the rest of the album they lead. They set the stage, tone and stylistic aesthetic for the entire project. The first tune is absolutely key to the success of a concept album. These 5 are prime examples of how that works. I have others, but this is enough for now ( I don't need to get started down this rabbit hole...)

Besides, I come to DT to get away from the 'organized noise' stuff I do for a paycheck.

I enjoy these threads much more as a lurker than an active participant.