Thank you ladies, you see this is my first baby so I'm really skiddish abt what I do and how it effects him. I have found that he likes country and some slow rock, which sounds funny but he does. Mostly though I play classical or country.
I've heard that somewhat soft and slower music is better, particularly harmonious, soothing music, like guitar, violin, piano, classical. Its recommended to avoid anything harsh or brash or discordant or startling. Its also strongly recommended not to use headphones or music directly against your belly as that amplifies sounds too loudly. I'd think bluegrass or country would be fine. I do a lot of classical or soft folksy stuff myself.
I like to play Amazing for my little girl. Its a great song!