Confused about basement finishing in New England...

Had a similar problem with my basement in CT. All I did was put an air conditioner in and it works better than any dehumidifier. My pipes in the ceiling don't get condensation on them any more. It stays dry all the time and doesn't smell either. Make sure to spray the walls with bleach to get rid of your mold. You do need to invest in gutters and make sure the down spouts are connected to underground pipes that brings the water far away from you house. Try the AC first, I think you will like the results and it's also the cheapest way to start. Make sure you get a big enough one.