Naples is a place few people think of first when traveling to Italy, and they're missing out. It's very safe [for the most part] and many people will help you as you use your Italian and they try their weak English. The food is better than the rest of Italy, no joke. The marinara and margherita pizzas are the best in the world -- literally.
It's easy to stay in an 'American' type hotel and get around on the metro or train, and you can always take a cab as well [like today, when there was a train strike and we were out in the countryside exploring!] Another thing to seek out is a sfogliatella frolla, which is a sweet cream center in a sweet pie crust ball [unlike the typical sfogliatella that look like shells]. Here is a recipe if you want to make some, send the extra to us!
Sorbillo is hidden away on Via dei Tribunali (near # 32, though it's the one with the stone engraved sign above it, not the blue/white awning) is the best place for pizza -- this is a '4 seasons' [quattro stagioni] one with vegetables and meats. It was literally incredible. The pictures don't reflect how perfect this wood fired pizza was: