Alexander's restaurant in the main square in Argostoli was so good, we ate there twice. The waiters are friendly, especially the Aussie waiter. The food is fantastic - you have to try the stuffed mushrooms and the beef stifado.
The setting here is lovely - apart from the noise from the racetrack over the road. The food is average, although my boyfriend (a vegetarian) thought it was really good. We had egg fried rice, sweet and sour vegetables, veggie noodles, and chicken in black bean sauce. I wish I had tried the crispy beef instead of the chicken.
The only thing I liked about the caves was the fact that you could escape from the heat down there. We had a choice to either visit the caves here or the underground lake at melissani - my boyfriend choose the caves, but I would have prefered the latter.