In reply to alps_p:
If you want family friendly beaches then try Solenzara on the east coast where the Bavella road hits the sea. That way you won't have secluded coves but will have the best accessible cragging on the island & plenty of sun, sea & beach. Camp site there does cabins right next to the beach. Porto Vecchio down the coast is prettier, busier & further away.
Up north on the west coast Porto area has not so child friendly pebble beaches & some back of the beach sports routes.
You would be hard pressed on the island to find a beach thats more than an hour from some climbing option. Falaises de Corse guide is full of crags, but for my money somewhere accessible to Bavella is your best bet.