Hey - Well, I worked out pretty much the entire pregnancy, and I listened to pop/rock while doing cardio. After birth, my so will light up when I play that playlist that's on my MP3 player. No kidding.
I first saw this when he was about 5/6 weeks old, and I was washing his bottles and him in his pack n'play in the kitchen with me. He was crying and I decided to turn on some music and sing to him. The minute that song "The Climb" came on, he quited down and clearly knew the song.
Seriously, it's happened again everytime I put that playlist on.....
If it's classics you, want, great. I went for the ROCK!