Ok, now I can finally say the song I'm rooting for: Revelations.
Back when I was a kid and starting to hear foreign and heavy music, after my first steps with hard rock (Bon Jovi, Guns n' Roses) Iron Maiden were my first exposure to heavy metal, and to this day they remain (regardless of how much I actually listen to them) my favorite band - Revelations started it all, it was the song that made me fall in love with Bruce Dickinson's voice, Iron Maiden and heavy metal in general. It started an avalanche effect that made me the metalhad I am still today. Also, I think it's actually a very nice and great song, an eclectic piece from Bruce and that is original both then and now.
So, pretty please with sugar on top, would you mind to save the song that is the most important one in the musical formation of a big Iron Maiden fan? I still have to vote in the Number of the Beast poll so in case someone wants to save Children or 666 I can help him voting against the other song