Would you help me with some classical music suggestions please?

I would love to know your favorite classical music pieces. I want to play them while I am pregnant, not because of the idea that it makes baby smarter but I really feel like she likes it. And I know I do. Unfortunately I have no classical music education and really don’t even know where to begin. The only song I really know (and love) is Fur Elise. Thanx in Advance.