Some examples of "Top 10" lists:

http://www.planetrock.com/music/backstage/the-rock-lists/the-greatest-ever-rock-song/

http://rateyourmusic.com/list/willhite3/top_10_rock_songs_of_all_time/

http://www.thetoptens.com/classic-rock-songs/

http://music.lovetoknow.com/myspace-music-codes/rock-music/best-rock-songs-all-time

http://ultimateclassicrock.com/top-100-classic-rock-songs/

http://www.rollingstone.com/music/lists/the-500-greatest-songs-of-all-time-20110407

http://www.rockonthenet.com/archive/2000/vh1rocksongs.htm

http://bwclausen.wordpress.com/2011/02/28/all-things-music-vol-3-top-10-classic-rock-songs-of-all-time/

An example of one person's criteria (note: this may be VERY different than your criteria!):
It has to sound like classic rock. Eric Clapton is synonymous with the phrase, but I do not consider "Forever Man" to be a classic rock song. Bob Dylan, and most songs sung by The Band, are not classic rock either; although they come close, I consider them folk. There is also an automatic disregard of anything sung by Cheap Trick or Poison; even though 101 the Fox (the station in Kansas City that calls itself a "classic rock station") insists on playing them. They just do not capture the sound. A classic rock song has to have a riff so familiar, you can recognize it in a second, and lyrics that the listener can relate to in some way; it cannot have a drumbeat that a five-year-old could play. Finally, it cannot be a cover, so sorry Hendrix, but "All Along the Watchtower" does not make this list.