As far as Northern New England goes... I have lived in VT, NH and ME and I went to school in MA. Boston has several of the nations best hospitals. IMO, if you aren't going to work in Boston, then the best hospitals are Dartmouth Hitchcock in Hanover (or is it Lebanon?) and Maine Medical Center in Portland, ME. They are the only hospitals in Northern NE that make the US News and World Report rankings. Maine Medical Center just completed construction on an new, enormous women & children's center also. Fletcher Allen in Burlington, VT doesn't get as good of reviews as the others I have mentioned, but Burlington is a really, really great place to live.
Boston, MA, Burlington, VT and Portland, ME are the only cities here that I would consider living in for the long term, I live in Manchester, NH right now. I am going to move away from NH the second that I graduate. I would never dream of raising children here or living here any longer than I have to. If I worked at Dartmouth Hitchcock, I would commute from Vermont.
I can't really tell you much about RI or CT, other than Providence seems like a cool city and Yale New haven is supposed to be a good hospital.