Hi there
We stayed in Calella de Palafrugell in May. Sorry I can't offer any tips re restuarants....we ate out twice - once at the restaurant right at the end overlooking the beach which was ok, and once next door at Toni's Bar, which was disappointing. Both expensive!
One thing I would recommend would be the market in Palafrugell on Sunday mornings. It seemed like the whole of the town turned out for it and the square right at the end of the market was really bustling, with all the locals sitting out on the pavement cafes. Really nice to sit and people watch!
Another nice place was El Bisbal, a town just inland from Calella de P. Really nice Spanish town with a lovely little square. It is a centre for ceramics etc.
The walk from Calella de P to Llanfranc was really nice as well.
Didn't use public transport as we had a hire car, which I would recommend.
Hope this helps!