Roatan is the most beautiful island we've seen. Most people from the cruise ships do not get to really see it unless they are willing to venture off on their own.
We had a group of 6. We took some risk and rented mopeds from Captain Van. We took a taxi to him and had previously made a reservation with him over email. He treated us right. Gave us a map and made suggestions where to go. He also provided us a trip back to the ship. (Via the back of a pick-up, which seemed like an easy ride after riding with "Reggie" in Belize.)
The mopeds go fast enough to stay with the traffic. You drive on the right side of the road there. People were very friendly where ever we went.
The native kids would love to sell you shells and such, and we wished we has bought more for the one US dollar they wanted after seeing the same shells in Grand Cayman for $20.
I took a taxi to West End, neat little town with shopping, restaurants, scuba stuff. Then went to West Bay beach which was beautiful, then back to ship. I found a taxi that cost $25 + $5 tip to drop me off and pick me up at designated times. If you do use a taxi - 1) don't get in for more than $5 or $10 per trip and have an agreed on price before you leave, 2) try to get one outside the gates, 3) go to Roatan websites and research rates and places. The gentleman I had was named Joseph, can't remember taxi #, think it started with 0. Please be an educated tourist!!
And watch out for the sand fleas, you don't realize you are bit until you can see in a mirror!! They don't hurt, itch less than a mosqito, and quite a few of us on the ship had them.