I wouldn't pass up the opportunity to spend the better part of a week perusing the National Museum of American History in Washington, D.C. But for a quick afternoon trip into the past, you can't beat the house museum down the road.
And we're lucky in New England, cause there are lots of them. But most are only open through early- to mid-October, so you'd better hurry and put on your driving gloves. It's time to discover the golden nuggets of local history hidden on the Main Streets and side-streets throughout Vermont.
The "Historic House Museums in Vermont" website, put together by the Victorian Preservation Assocation, is an excellent tool for planning your tour: http://www.vpa.org/museumsvm.html.