I live in central New Hampshire, Within 10 minutes of Squam Lake ( the movie "On Golden Pond" fame). It is very nice, but there are many powerboats. You almost never have the lake to yourself. Having said that, it is still a beautiful lake, and I am very fortunate to live so close. (43°48'01.87" N 71°33'55.07" W)

My favorite spots are in Adirondack Park of New York.
Lake Lila (44°00'33.33" N 74°45'55.20" W) is wonderful. A friend and I had the whole lake to ourselves one weekend the end of October. I took the "Sunrise from Canada Island" photo.

Lake Champlain is loaded with American history. From the French/Indian wars to the War of 1812, several Islands have informational and commemorative plaques.
Crab Island (44°39'45.69" N 73°25'00.83" W) anchored the right flank of the American Fleet in the Battle of Plattsburg, War of 1812. Here is a GPS track and some photos of my kayaking trip to Crab Island, last summer: http://www.wikiloc.com/wikiloc/view.do?id=1909646
Valcour Island (44°37'19.86" N 73°25'48.99" W) is easily accessable and was the site of a naval battle during the Revolution.
Carlton's Prize (44°36'17.37" N 73°20'48.32" W) was the the site of a rather amusing naval "engagement", that was "fought" the day after the Battle of Valcour Island.