Ugh. hehe, Fanueil Hall isn't where the locals go...it's like asking a New Yorker to go to the Empire State Building. Though I went there once in high school and made fun of tourists. We were really bored that afternoon I guess.
In place of Fanueil Hall, I recommend the North End for food, the MFA and Isabella Stewart Gardner Museums for touring, or the Freedom Trail, or the churches and huge library in Copley Square. And Downtown Crossing for shopping instead of Fanueil Hall. Also, the Science Museum has a cool CSI exhibit right now (according to two friends of mine from school who were tourists this week) and the Aquarium is pretty amazing. If it's still unseasonably warm, take a stroll in one of the city's urban parks, called the Emrald Neclace - I recommend the Arnold Arboretum (renting bikes could also be fun for there) or Forrest Hills Cemetary. And the Sam Adam's factory does tours if you're interested.