Boston Help, Please!

I'm in the process of planning our trip to Boston in a few weeks (!!) to see my Dad run in the Boston Marathon! However, I've never been to this city or anywhere near it, so if ANYONE is from around there or has visited, please let me know your tips! Restaurants, tips for navigating, etc. We definitely plan on doing the Freedom Trail, and Kurt and I are going to see Orchard House (Louisa May Alcott's home), but that's all I have right now. Our time will be limited, but I want to know your thoughts if you have any! :)