Been giving this some serious thinks over the last couple of days, and this is my list to add to many of those above:-
Jumpin Jack Flash (Live) Johnny Winter
Moonage Daydream from Bowies Ziggy Stardust - guitar work from the sadly missed Mick Ronson, an awesome musical talent.
I suppose you can't have guitar solos without Clapton so
Crossroads - Cream (hugely complimented by the bass work of jack Bruce)
And you can't mention the guitar without considering George Harrison and Pete Townshend. Now whilst not really known for spinning out an elongated guitar solo, their great guitar work can be heard in
While My guitar Gently Weeps - Beatles
Quadrophenia (track from the LP of the same Name) - The Who