I don't do this so much anymore, but when I was a child living upstate whose only glimpse into musical theatre was to discover new cast recordings, that's literally what I would do all night long, and on the weekends.
Some of my fondest memories were laying on my bed just listening to random recordings I was able to find at some of the bad local CD stores that never seemed to carry theatre recordings.
So, with that said, my DROWSY CHAPERONE (as a child, atleast) would be CATS, first and foremost, followed by HELLO, DOLLY!, FOLLIES, MISS SAIGON, LES MISERABLES, THE SOUND OF MUSIC, and SUNDAY IN THE PARK WITH GEORGE.
"If you are going to do something, do it well. And leave something witchy."
-Charlie Manson