I like Somerville. Belmont Wheelworks is in the next town over, but I think of it
as Somerville. It's a huge shop, with tons of goodies, that spill over into another shop around the corner.
Somerville has some of the best coffee on the East Coast.
Red's Barbeque is so cool it has bicycle valet parking.
If you are new to Boston... we will need to know what your interests are. There's
a ton of museums and shows and things to do.
I also like Cambridge. You can find a fistful of bookshops there, a decent hifi store, a tea house, good mexican food, great ice cream (there's this one place that has the craziest flavors you ever saw, if you see it, try some), a terrific home cooking style place. And more... on the way in town from Boston you pass a shop that sells games. It's one of only a couple places on the Eastern seaboard you can buy a decent Go board. They even have good Go books.
I love the Boston Aquarium.
Btw, you can get anywhere pretty easy.