If you were to sum up the city of Rome in two words, they would be "busy" and "historic". Today Rome is one of the most important tourist destinations of the world. I think, you'll make a right choice, if you go to Rome. 

First you should go to the Colosseum-the enduring symbol of ancient Rome. Today, the Colosseum is used for religious purposes. The Pope leads a procession on good Fridays called the station of the cross. The Colosseum of Rome has been given great importance by the media and that is the reason why a lot of Hollywood movies had been shot in this amphitheater. 

Your next stop can be the Capitoline Hill. It is a great place to get a view of the Roman Forum. The focal point of the hill is the grand Piazza del Campidoglio designed by Michelangelo. There are two important museums housing an impressive collection of sculptures, paintings and mosaics. 

Rome is a great city for walking. There are a lot of walking tours around Rome and the price is about 40 euros per person. You can take a lot of amazing photos, but you should be careful of pickpockets on crowded streets. 

So, I believe you'll enjoy the trip and my advice will be useful.