Great place to explore on your own. Walking on the wall is a must, but requires care on all the steps, some of which are steep and can be slippery. ...
We took the local bus from the terminal in front of the ship. $12 Kuna each way. Bought return tickets. Walked the wall and ate lunch at a nice restaurant on one of the side streets. Would not miss walking the wall. The local bus took us to the same place as the ship transfer bus and we had no problem finding the bus right in front of the entrance to the old town. ...
We used one of the guys arranging taxi's who appear at every port to transport us to town and spent a while in the Old Town followed by a reasonable priced drink at a café which took Euros. We did need some local currency but most places take Euros. A lovely port and very friendly people. It feels very safe and was also very clean. ...
I found Dubrovnik to be lacking in any atmosphere at all, and with no distinctive Croatian shops/items on offer. I walked the walls and took the cable car on my own, which was easy enough, but overall I was disappointed with this port - actually being there didn't add anything more than you'd get from looking at photos! In contrast, Split and Trogir were much much better and we visited them later ...