Is there a central hotel to stay at? I don't want to commute from New Hampshire every day.
Unfortunately there is no meet hotel or otherwise central hotel. If I had to recommend an area, I'd say anywhere in Cambridge, or near one of the T stations. The buses are also pretty reliable, if you check for Google's public transit options to get around.
I'm commuting from New Hampshire most or all days (might stay with my daughter in Boston one night) if you are interested in car pooling.