Boston is awesome. We spent three nights at the Hyatt (close to the Opera House) and jammed in as much as we could.
Sunday: We took the trolley tour around town the day we arrived. It was raining pretty heavily so it was a nice option to learn a few things and stay dry. We ate at Durgin Park the first night as @Yukari recommended and really enjoyed it. Great prime rib. A lot of charm in that place.
Monday: Spent the morning and early afternoon shopping in Wrentham and Patriot Place. Ate dinner at Summer Shack (@Ernest Jones), explored Quincy Market, Newbury Street, and had a beer at Cheers.
Tuesday: Took the train to Harvard, toured Fenway, and checked out the aquarium during the day. I was pretty gassed at that point, but had to keep going. We had dinner at Boston Chops and it was probably the best steak I've ever had. A bit pricey but overall good experience. From there, we took the train to the Garden for Bruins Game, then out for a couple of beers close to the Garden.
One thing I have to mention is that I was really impressed by how welcoming and nice the people of Boston are. Everybody we spoke to that knew we were from out of town seemed to want to represent the city well. They did a great job. I'll definitely be back soon!
(St. Patrick's day maybe)