http://www.hotels.co.uk/hotel-italy/hotel-rome /hotel-raphael/
This is a lovely 4 star just off the Piazza Navonna in a pretty area. It's a really nice hotel furnished with antiques and very, very central.
http://www.albergosantachiara.com/ This is a hotel I have stayed in just behing the Pantheon. Wonderful position and fantastic to come out in the morning and sit having a coffee facing the Pantheon. Also very central.
The beauty of both hotels is that they are right in the centre and you can walk to everywhere and also get back easily and take a break during the day to rest a little or change shoes - Rome is beautiful but can be exhausting and it is great to go out in the morning - come back for a siesta - then out again & back to change for the evening. If your hotel is further out you tend to have to stay out all day.