I always recommend two places close to Fenway on Beacon Street and right on the Green Line T ( Boston College, Beacon Circle line ).
Out near Temple street on Beacon Street there is a motel. It has been a Travel Lodge and a Holiday Inn Express. Not sure what it is now. You can hop on the T and be at Fenway or Kenmore square in five minutes.
There is an excellent Mexican restaurant on Beacon near the corner of Park Drive.
This is authentic Mexican and the food will make your tongue hard.