Well, I make it my mission to proselytize reunion era Maiden. I figure most people in the metal world are at least somewhat familiar with a couple of their classics. So if they're not on somebody's banned list, there's usually a reason. Often it's that they heard something like Run to the Hills or The Trooper and thought it was good but didn't really transcend being typical 80s metal (for prog fans, this can cause them to just not give the band a second look). Or maybe they don't particularly enjoy high-pitched male vocals. And I think most people who aren't familiar with Iron Maiden aren't really aware of the reunion era and the way that they went in a different, much more prog-heavy style (and, for the people who don't love high-pitched male vocals, Bruce sings in a lower octave). So I always try to send something from the reunion era, usually one of the longer reunion tracks.
As far as picking out When the Wild Wind Blows specifically: really, I'm just experimenting with different things. I think there are probably about ten longer reunion-era songs that are pretty good ones to send (Dream of Mirrors, Paschendale, Brighter Than a Thousand Suns, For the Greater Good of God, The Legacy, Isle of Avalon, Starblind, The Talisman, When the Wild Wind Blows, The Red and the Black, The Book of Souls—Empire of the Clouds is just as good but too long for a standard roulette round), so it's really a matter of just deciding on one. I went with The Legacy last time I sent Iron Maiden, I think to Shadow Ninja, and I considered going with The Legacy again, but I thought I'd switch it up. Wild Wind was a clear one for me to turn to next, since it's the first Iron Maiden song I ever heard. I also considered The Red and the Black until I realized it was above the time limit.