Looking for a hotel in Rome for one night- 2 adults and 2 teens....difficult to find rooms that accommodate 4...what area do we want to be in that's lively & where we can walk around immediate area, get dinner?

Albergo del Senato has a mini-apartment that may work for you. It is right next to the Pantheon so you will be close to Piazza Navona, Trevi Fountain and the square out front is lively. If you are there in warm weather, the rooftop bar has an incredible view of Roman rooftops and the Pantheon.

I don't know about room configurations, but I love the Hotel Modigiani.

Same area, near Piazza Navona and Pantheon, look at Palazzo Navona. It is on a quiet side street, modern design interiors, roof top bar as well a bar off lobby. I saw a large family room on our floor. Loved this hotel! Book a dinner reservation at nearby Armando al Pantheon well ahead of leaving home.

The Hotel Fontanella Borghese has at least one quad room. The hotel is at the end of the Via Condotti, about halfway between the Spanish Steps and Piazza Navona.

http://www.fontanellaborghese.com/en/

The sister hotel of the Fontanella Borghese has the option of connecting rooms. Hotel Due Torri is a few blocks from the FB, in the direction of Piazza Navona.

http://www.hotelduetorriroma.com/

The Alimandi hotels have quad rooms. Their breakfasts are delicious. They are a stone's throw from the entrance to the Vatican Museum.

The Alimandi is now called the Hotel Museum:
http://www.hotelmuseum.it/it

I stayed there earlier this year. The hotel was fine, breakfasts were odd if you want anything besides pastries, and the guy who ran the breakfast room was unpleasant.

http://www.hotelmodigliani.com/en/appartamenti.html

I am sorry to hear about the changes at the Alimandi. My family and I stayed in both their 3 star and 4 star hotels and have good memories of our time there.

Www.booking.com shows plenty of quad rooms in Rome. Enter "Rome center" as your destination, or a specific neighborhood such as "Trevi Fountain". Indicate that you are four guests and want one room. Look for hotels with a high guest rating (around 8 or above), based on more than a few guests, and in your price range. Read the guest reviews.