Most achingly-beautiful music

Akino Arai - Furu Platinum - Orange Noel -
Japanese Female vocalist with the prettiest voice in
the world, and the best arrangements ever.

Most of her career has been spent singing theme music
for anime movies, and TV show theme songs.

Most excellent choice Quirkasaurus.
How much BoTox do you think she needs to pantomime the anime?

John Williams rendition of Joaquin Rodrigo's Concierto de Aranjuez on RCA Red Seal.

Summertime - Louis and Ella from Porgy and Bess

The look of Love - Dusty Springfield from Casino Royale (Burt Bacharach)

Besides the three I would like to mention some others which I had great difficulty in putting it in runners up.

Fur Elise - Beethoven

Moonlight Sonata - Beethoven Radu Lupo, Israel Sypmphony Orchestra

The four seasons - Vivaldi - Joseph Silverstien, Seiji Ozawa, Boston Symphony Orchestra

Beethoven's 9th Symphony - Seiji Ozawa on Telarc

The girl from Ipanema - Antonio Carlos Jobim, from Getz/Gilbarto

Childrens Games - Antonio Carlos Jobim - Stoneflower

Lara's Theme - Maurice Jarre Original Soundtrack from Dr Zhivago

A man and a woman - Francis Lai Original Soundtrack

There are many others but it would not be appropriate from me to compile a huge list here. I hope I am not forgetting some other superb inspirational and soul stiring music.

I just cannot forgive meself for not having mentioned this beautiful piece of music

Gaeltacht - Renaissance of the Celtic Harp by Alan Stivell.

A masterpice of celtic music.

CLASSICAL:
Satie--3 Gymnopedies
Bach--Air on G-String
Mozart--Concerto #5 for violin & Orchestra, Adagio
Beethoven--Symphonie #6--Shepherd's Song

JAZZ:
Oregon, Silence of a Candle from Beyond Words
Paul Winter, Icarus
Bolling, Sentimentale from Suite for Flute and Jazz Piano
Pat Methany, last 3 songs on Secret Story
Oscar Peterson, Blues for Lisa from The More I see You

ROCK
Traffic, Freedom Rider from John Barleycorn
Eric Clapton , Tears from Heaven from Unplugged
Jackson Brown, Late for the Sky from Late for the Sky
Grateful Dead, Ripple from American Beauty

WORLD & MISC
Nusrat Fateh Ali Khan, My Heart, My Life from Night Song
Loreena McKinnet, Bonny Portmor from The Visit
Ana Caram, Correnteza from The Other Side of Jobim
Ali Akbar Khan, Fantasy from Journey