There is so much to do in Rome, that I was only able to see a few of the essentials in my 1 day in Rome. Of these, the sites not to be missed are: Roman ruins—including the Colosseum, Piazza Navona, the Pantheon, the Trevi Fountain, and the Spanish steps. My recommendations: take a tour at the Colosseum—I found ours to be highly informative and interesting; sit at a café in the Piazza Navona and soak in the atmosphere; enjoy some gelato while sitting on the Spanish steps.
Quick Tips:
If you want to go to Vatican City, either be prepared for an extremely long wait for entry, get there early, or pre-book a tour. We drove by the entrance to the Vatican City museum on our way to the hotel. Our taxi driver informed us that the line was probably about 4 hours long at that point (10am).
Food from the carts around tourist areas is a good, quick way to satisfy hunger while on the go. We chose one by the Colosseum that served paninis. The sandwiches, in addition to being delicious, allowed us to continue our sight-seeing without taking a lot of time for a meal.
Best Way To Get Around:
Taxis can be very expensive; our taxi from the airport to our hotel cost €75 (not including a tip). The meter seemed to rise every 5 seconds. The public transportation within the city is efficient, inexpensive, and fairly easy to navigate.
Having said this, we had a little difficulty in determining how to purchase a bus ticket for, but the bus driver just waved us to sit down when we got on. The bus was fairly crowded mid-afternoon on a Friday when a girl covered in shaving cream entered the bus. Nobody seemed to think this was an odd occurrence. We learned why the next day. It had been the last day of school for many kids and being sprayed with water, shaving cream, and other items is not an unusual ritual for them.
The metro was a smooth and easy system. The only complaint I have is that all of the ticket machines on the entrance level were broken. However, when we took the steps down to the track level, we were able to find working machines. The cost for a 75 minute ticket was €1.