A long time ago, I made a tape of songs with my favorite guitar solos. I don't remember all of them (and I'm pretty sure the tape was made before DT broke in '92), but I know at least the following were on the tape:
Iron Maiden - The Trooper (primarily for Dave Murray's solo where he used the whammy bar to make a horse-like sound)
Rush - Limelight and the "Presentation" section of 2112
Ozzy - Crazy Train (aside from the solo, I love the relatively simple, descending bass line underneath)
Yes - Roundabout (Steve Howe's two solos towards the end of the song, which are interspersed with keyboard solos, are fairly short, but both are very effective)
Dio - Rainbow in the Dark
Helloween - Halloween (the long harmony/unison solo towards the end is all kinds of awesome)
Rainbow - Stargazer