hard to tell. Be prepared to be a bit squished. Butts were apparently smaller back in 1912.
There's a really tasty Greek place called Saloniki a block away from the park. I'd never seen anything like it before. It's a Chipotle/Moe's/Cafe Rio style place, but they're building you Greek food, not Mexican. My wife and I went twice on our Fenway weekend we liked it so much.
The tour is pretty cool if you have time, but there's plenty of other stuff to see in Boston, and unless you're there on an off-day, they won't take you anywhere on the tour you can't see walking around the park before the game. Anybody who works there is so proud of the place, they'll volunteer all the little bits of trivia the tourguide would have.