The union oyster house sucks. Good luck not getting into a fight in fanuel hall area.
Mikes pastry is A good tourist place on Hanover street and also at the beginning of the north end.
Take a tour on the freedom trail, a bunch of them start around the park street t area.
The tam on Tremont is a good dive bar or it used to be. they use to keep hotdogs at the end of the bar and bums would come in. Drinks are cheap and everytime i was in there the guy girl ratio worked, but I haven't been in over a year and I heard things changes.
The Isabella Gardner Muesem is great, they just expanded, great date spot if you are traveling with anyone. It's over in the Fenway area.
Harvard sucks, I hate that whole area, bunch of liberal fucking hippies with hairy oysters.
I would go to Salem, 30 min train ride from north station, good bar scene, the chicks are easier and less snobby than Boston, plus you can check out some of the witch trail stuff. When I was living in Boston I would actually go out in Salem over the Boston scene.