hmm, not much to go on.
Probably the best hotels imho are 15 Beacon (edge of beacon hill - close to Back Bay and Faneuil Hall, Finanacial District, the Eliot Hotel (edge of Back Bay, a cab or the T to Faneuil, North End, Financial), 2 Ritz's (go with old (Boston) for better location (Back bay right next to public garden) not the new one (Boston Common), four seasons (nest to public garden, edge of BB), nine zero (botique near financial district and faneuil).
There is a Westin and a Sheraton for *wood - both in heart of the Back Bay. Both decent, but no means fantastic.