Strangely I booked to stay at a different hotel, however for reasons which are still not clear to me my reservation was changed to the Hotel Atlantico. I couldn't be happier about this! The hotel is in a perfect location right next to Termini. Thus you have access to the Metro, buses and open top tour buses as well as being able to walk to all major attractions. The Metro in Rome will not take you into the Centro Storico but buses do. Reception will tell you the numbers you need. We found them very easy to use and useful, as at 6.5 months pregnant I wasn't keen on walking far.
Breakfast at this hotel was great - a good choice; fruit, yogurt, cereals, bread and pastry products, eggs, cheese, ham, and a couple of cooked items. Amazingly they also do a good cup of tea (how British am I?)!
The staff on reception and the porters were extremely helpful and friendly.
The only slight downside was that we had a room facing onto the street and there was traffic noise. Take ear-plugs or ask for a room at the back.
We loved the Art Deco decoration!
Also - you need to be aware that you are staying in Rome and therefore you will be paying more for a hotel than other European cities. Accept this and enjoy yourself!