"Check out Anthonys Key (sp?) in Roatan then but you can have a great time in Belize also. Belize would probally be more safe also."
Agree that for traveling with a non-diver AKR would be the best bet on Roatan, more there to do and the botanical garden is about a block away.
Belize City is a slum and not safe at night or for your wife to be walking around alone during the day plus the best diving is offshore from one of the islands but not sure about the nightlife on them.