An Audio Guide to Ancient Rome and its companion website which adds a helpful map and sensible tips for your visit, is an audio resource I highly recommend for you to use while visiting Rome. Subscribe to the podcast, download the episodes, and you'll have a high-quality museum-like audio guide to the historical sites throughout Rome. Listen to each episode while you're actually at each site for the ultimate experience.
History of Rome Podcast is a superb 70-hour audio-book detailing the history of Rome, from the founding of Rome in 753 BC to the fall of the Western Roman Empire in 476 AD. I highly recommend this.
The GET READY FOR ROME! podcast provides many interesting insights into Rome by a college professor who lived and taught in Rome for ten years, and travelled there with students for many more years.
Rome: The Rise and Fall of an Empire (History Channel 14-part series) is very strongly skewed to the military history of Rome, but hey, if you already subscribe to Netflix DVDs, it's free.
Roman Holiday, the best movie photographed in Rome, ever, I rate it 9 out of 9.
La Dolce Vita, the best movie to give you the feeling of Rome, ever, I rate if 8 out of 9, but it might take you several watchings to "get it", like it did me.
The Great Beauty (La grande bellezza), a spectacular new (2013) movie which features Rome prominently. It's a modern version of La Dolce Vita, with gorgeous photography.