I can still attest -- last Friday -- Baseball Tavern still serves the BEST fried clam plate in the area.
The BT, BBW, Cask -- a true sports bar experience.
If you only have six hours free -- unless you have a Duck Tour / Old Town Trolley tour ticket, have a great dinner and walk back up to the park.
One of the things that I get irked at is people come to Boston, thinking only about Fenway. There is SO MUCH MORE here than Fenway Park. And in the summer, so much to do.
I always recommend - spend the extra money on a hotel room IN TOWN. If you can spend three or four days -- do so. That gives you plenty of time to attend one or two games at Fenway, also to take the park tour, and see other things.
MFA? Aquarium? Museum of Science (great for kids)? A night at the Symphony or Pops? Walking the Freedom Trail? Dining in the North End? The waterfront? The USS Constitution - also great for kids - and FREE. The Christian Science Church area -- marvelous park to visit. Trinity Church. Copley Square. "Top of the Hub" at the Pru. The Old State House. Occasional free shows at the Hatch Shell.
There's so much here to see. As a "native" there are still things on my "bucket list" to see that I haven't seen yet.