Imho Salem is a horrible tourist trap. Unless you're into the roadside attraction level kitsch skip it (and if you are, you'll love it).

Idea for a solid day: Currier's orchards in Merrimack -- pick some apples, get cider donuts. Head over to The Bistro at LaBelle -- in Amherst for a tour of the winery, tasting, maybe lunch/brunch (may need reservations not sure). Uncanoonucs in Goffstown -- Take a hike up either or both; enjoy some fall colors. Maybe take a picnic lunch up to the top. Head over to a nearby brewery of your choice for a flight or a pint and/or a bite.