It's a bit tricky to travel in the Islamic world during Ramadan. Most restaurants are closed during the day and people end up lethargic by the end of the day.
Iftar, the fast-breaking meal served at the evening call to prayer makes the daytime fasting worth it. Each night for the month, feasts are served at sundown. Booking a table for the buffet dinner at any hotel in Abu Dhabi will do, but I particularly enjoyed Le Royal Meridien where they throw big tents over their outdoor pool during Ramadan and serve their dinner in an air conditioned wonderland of Middle Eastern cuisine, mounds of date, and Arab sweets to fill in all the cracks.
Each country has slightly different rules about eating, drinking, and dress during the holy month. In Abu Dhabi, everyone is expected to dress a little more conservatively (covering knees and shoulders) and it is not allowed to eat or drink anything in public between sunrise and sunset. If you do not practice Islam, it's wise to carry a small bottle of water in your handbag and sip privately throughout the day.