We spent the day in C too on our last cruise. It's a charming Italian town. There is a main street with some nice Italian shops e.g. Furla.
There is also an outdoor market that sells houehold goods/clothes/fruits and vegetables.
It wasn't tooooo exciting but we spent a pleasant half day wandering around and then back to the ship.
For Taormina, we got there in August 2003 when those terrible heat waves killled hundreds of Europeans. It was 115 degrees!!!!! We went up to Mount Etna (lunar landscape - I didn't find it too interesting) where we wore a sweatshirt for the first time in weeks. Nobody went up to Taormina because of the heat. Most people got off the tender and got right back on and went back to the ship because of the heat.