She's saying PANTHEON, not PARTHENON.
Of course, as a 19-year old backpacker in Europe, my brother and I spent a morning in Athens Greece looking for the Coliseum......we went all the way out to a soccer stadium on the bus that was called "The Coliseum".....that night after reading our guidebook we realized we were looking in the wrong city! We still laugh at our idiocy.
I think you would be happiest with the atmosphere if you stayed in the Pantheon or Piazza Navona area. These are very picturesque areas, that are what you think of when you think "Rome". Winding, cobbled streets, tiny shops, picturesque fountains, sidewalk cafes. Traffic is not as heavy and diesel-choked as by the Termini. Also, in this area you can walk to the Forum, Trevi Fountain, Spanish Steps, etc etc etc as well as being surrounded by sites you want to see (The Pantheon, Piazza Navona....). By staying here you can wander peacefully at night (very safe, you can even walk down to the river which is magical at night) and absorb the atmosphere, rather than having to hop on the subway and go from your hotel to the sights. You will be right in the middle of the sights! For a very short visit, I think this would be extremely worthwhile.