If you go to the visitors center at Independence Hall, they have plenty of guided tours. If you want to go inside Independence Hall, get there early in the morning as tickets go fast. We did the Duck Boat Tour, but in light of the accident they had two weeks after we were there, I'd avoid it if they're even still running it. They have a walking tour we almost went with.
Burn down the disco. Hang the blessed DJ. Because the music that he constantly plays, it says nothing to me about my life.