I love Durgin Park (if you're talking about the one in Faneuil Hall marketplace). Awesome fish cakes and beans.

The 17-55 f2.8 IS is the way to go if you can swing the cost. And the Doc is right, the 85mm f1.8 is a very cool portrait lens. Just understand that you'll need some distance between you and your subject. I have the 35mm f2, the 50mm f1.4, and the 85mm f1.8 and the vast majority of my indoor kitty portraits were shot with the 85. It does a great job of removing distracting backgrounds and creating intimate portraits. It all depends on how much room you have to shoot.

I tried the 70-200mm f4 non-IS, but as I've gotten older I find it hard to keep a steady image at 200mm. That's just me, though. Other folks have no problems at all. But I'm holding out for the IS version in a few months, after I get the 7D and let the wallet recover.