Just about Anything by Pink Floyd.
The Entire "Dark Side of the Moon" album
"Wish You Were Here" is good as well
Some of the stuff from "The Wall" like "Hey You," "Mother," and "Is There Anybody Out There" are phenomenal as well.
Much of the "Meddle" album like "Echoes," "A Pillow of Winds," and"San Tropez" soothe me.
Some of "Animals," especially side 1 really makes me feel good.
Lots of bluesy stuff like Stevie Ray Vaughan, His version of "Little Wing" is fantastic, as is most of his first "Greatest Hits" album.
BB King, Howlin' Wolf, etc.
Simon and Garfunkel is great.
Santana, "Maria Maria"
"Al-Di-La" by Jerry Vale. Beautiful song.
Some of the Cleaner, Acoustic stuff by Black Sabbath, a la "Planet Caravan," "Solitude," "Laguna Sunrise," "Fluff," "Don't Start (Too Late)"" and the like are good.
There's a cover of the Rolling Stones' "Wild Horses" done by a female singer, I think it's Allison Krause? It was featured in a Season 3 Episode of "Buffy" as well as the episode of "CSI" where Sara finds her boyfriend Hank is a cheater from Season 3 called "Crash and Burn.
I'm normally into a lot of the loud and fast Heavy Metal/Punk Rock type of stuff like Motorhead, Early Metallica, Ozzy Era Sabbath. However, when I'm in the mood to chill, turn the lights off and take a hot soothing bath, etc. That's the stuff I listen to.