Near Stazione Termini -- Despite a handful of pricey choices, this area is most notable for its concentration of cheap hotels. It's not the most picturesque location, and parts of the neighborhood are still transitional and edgy, but it's certainly convenient in terms of transportation and easy access to many of Rome's top sights.
Near Via Veneto & Piazza Barberini -- If you stay in this area, you definitely won't be on the wrong side of the tracks. Unlike the area around the dreary rail station, this is a beautiful and upscale commercial section, near some of Rome's best shopping.
Near Piazza Navona & the Pantheon -- Travelers who want to immerse themselves in the atmosphere of ancient Rome, or those looking for romance, will prefer staying in this area to the more commercial Via Veneto area. Transportation isn't the greatest and you'll do a lot of walking, but that's the reason many visitors come here in the first place -- to wander and discover the glory that was Rome. You're within walking distance of the Vatican and classical ruins, as well as many bars and cafes.
Near Piazza del Popolo & the Spanish Steps -- This is a great place to stay if you're a serious shopper, but expect to part with a lot of extra dough for the privilege. This is a more elegant area than the Via Veneto -- think Fifth Avenue all the way.
Near the Vatican -- For most visitors, this is a rather dull area in which to base yourself -- it's well removed from the ancient sites, and it's not a great restaurant neighborhood. But if the main purpose of your visit centers on the Vatican, you'll be fine here, and you'll be joined by thousands of other pilgrims, nuns, and priests.
In Trastevere -- Once upon a time, tourists avoided Trastevere, but today, although it's off the beaten track, it's becoming more popular as an up-and-coming neighborhood where you can experience a true slice of Roman life.
