As requested, the "fully flexible" itinerary:

ITINERARY--ROME, 2010 TRIP

March 16, 2010 (Tuesday) Fly out from San Francisco
March 17, 2010 (Wednesday) Arrive in Rome. I will pick you up at the airport and bring you "home" so you can fall into bed.
March 18, 2010 (Thursday) Open due to potential jetlag.
We can walk the neighborhoods to get our
bearings, stock up on food, visit Piazza Navona
Campo d'fiori
March 19, 2010 (Friday) Ancient Rome--Coliseum, Forum, Arches of Constantine and Titus, Palatine Hill, Mamertine Prison

March 20, 20l0 (Saturday) National Museum, Pantheon, Baths of Diocletian, Spanish Steps, Trevi Fountain

March 21, 20l0 (Sunday) Capitoline Museum, Trajan's Market, Column, Victor Emanuel Monument and Elevator

March 22, 2010 (Monday) Pompeii, Herculaneum, Naples, Archaeological Museum

March 23, 20l0 (Tuesday) Villa Borghese, Museum and Gardens, Etruscan Museum, Cappuccin Crypt, Catacombs of Priscilla
March 24, 2010 (Wednesday) Tivoli Day Trip, Hadrian's Villa, Villa d'Este

March 25, 20l0 (Thursday) Vatican

March 26, 2010 (Friday) Ostia Antica

March 27, 20l0 (Saturday) Trastavere, Jewish Ghetto, Hadrian's Tomb

March 28, 2010 (Sunday) Appian Way, Catacombs

March 29, 2010 (Monday) Open

March 30, 2010 (Tuesday) Open

March 31, 2010 (Wednesday) Leave