Some of my favourites which you haven't mentioned:
Romeo & Juliet - Dire Straits
Love of my Life - Queen (live version)
Vincent - Don McLean
Tears in Heaven - Eric Clapton
Almost OT:
Ave Maria - Franz Schubert
Andante in C - Mauro Giuliani
A few years ago, Total Guitar magazine featured some brilliant pieces - Bohemian Rhapsody
, and some lovely stuff by Colin Reid (Tales of the Unexpected, Music from a Found Harmonium, etc).
Finally, have you checked out all of Kirk's stuff?