I'd advise the town of Narita, too.

It's a 15-minute ride, it's walkable, and even though it's not Tokyo, it's definitely Japan. You can enjoy the large temple at the center of town and wander the streets, people watching, enjoying a meal or two and poking around in the stores.

The best part of it is that you won't have to keep wondering if you're going to be late for your flight.