(1) Must be a popular song that most people in your generation (or wanna-be generation) would recognize. Thus, no jam albums or obscure Van Halen songs.
(2) Killer guitar solo.
(3) Wayne's World rule applies: no Stairway to Heaven.
Nominations off the top of my head:
Reeling in the Years--Steely Dan (Elliot Randall, I believe, is the guitar player)
My Sweet Lord--George Harrison
Ramblin Man--Alllman Bros (Dicky Betts)