The street next to our apartment was very, very noisy (especially in the evenings to about 3 a.m.), but we were so tired after all day, that didn't have many problems with falling asleep. If I was there without small child, I'll be sitting in one of the restaurants, I supposed:)
Everything! The apartment, Mondello, shop with vegetables, great restaurant with polpo just from hot water only with lemon, beach with sand really near from apartment, the warm sea and great rocks, Palermo, Monreale and Cefalu... The owners are very friendly and helpfull (small dificultie that they don't speak english, but answering in english for sms:) My son (5 year old) really loved great patio connected with apartment with trees and flowers, you can eat there in fresh shadow or sit there late in the night. We felt there at home. It was great.