Stairway to Heaven...come on people!!! Other then that Freebird, Don't Tread on Me, Achilles Last Stand and The Rover.
Child In Time by Deep Purple has an awesome guitar solo. The one at the end of Sultans of Swing by the Dire Straits is also cool.
Check out Larry Carlton's intro solo on Don't Take Me Alive, Steely Dan. Oh joy Please Register or Log in to view the hidden image! Also Buck Dharma's plaintive solo on the Last Days of May, from Blue Oyster Cult's live On Your Feet Or On Your Knees album.
Dragonforce have many, many good solos if you are into pretty hyperactive and glorious stuff. Check out this mp3 3/4 way in. (Sound + Video... Mp3... My Spirit will go on)
Band of Gypsies (Jimi) with 'Who Knows' Alabama with 'Free Bird' Simon and Garfunkel with 'Me & Julio Down by the Schoolyard' (more of a whilstle/guitar) And of course, the intro to Metallica's 'Enter Sandman.' The last one is extremely near and dear to my heart, as it is played for the intro at Virginia Tech football games. See here for a small taste. Watching that video still gives me chills, its absolutely amazing to be in that environment, you're yelling at the top of your lungs, but you still can't here your self over everyone else. There's nothing like it, and I don't think you could ever really understand unless you've been there for it.
Alvin Lee's (with George Harrison on slide) The Bluest Blues. It teh pwns all guitar solos. Love the emotion. Help Me is another good one, although all of his stuff is awesome, heh. - N
Okay, it's time to say this. Take into account the level to which rock and roll had so far evolved, the state of the art in rock and roll guitar solos, and imagine what this sounded like at the time: Johnny B. Goode by Chuck Berry.
Zappa - Inca Roads Trey of Phish - David Bowie Hendrix - Machine Gun Paco de Lucia - La Estiba; first track off Guitar Trio Al DiMeola - Majestic Dance (with Chick Corea and band)
The solo on Van Halen's Dancing in the Streets. Pages solos in Ten years Gone or Travelling Riverside Blues!
My favourite guitar solo would have be the Island in the Sun VCD clip, by Weezer. It's very short, but soooo upbeat, melodic, just genius. Dunno if it even classifies as a true solo: http://weezernerds.com/av/iitssolo.mp3
If you like guitar solos listen to Dragonforce. Cheesy name, but these guys can play their instuments. Its a fast metal band, no screaming, and catchy all at once. Check it out, some of you may be suprised.