What town are you staying in?
The possibilities of things to do are nearly endless...
My favorite farmers' market is Shelburne, on Saturday mornings. Second place I would give to Burlington...not sure the timing as I rarely make it out there. Make sure to try Rookie's Root Beer, at most farmers' markets, they are a husband-wife company whose products are a nearly-religious experience in incredible taste, especially the original root beer.
If you like hiking and/or photography, the views from some of the state parks (especially Mount Philo) are incredible and can be had with just a few planned hours on the trail. Underhill State Park offers more challenging trails but due to overhead canopy and the backside of Mount Mansfield, views are limited until you get quite a way up.
Be aware that Ben and Jerry's (the main place, on Route 100 in Waterbury) during the summer is like Walt Disney World...complete parking lot chaos, tour buses and slow-moving pedestrians everywhere, mile-long lines, etc etc etc. After you've spent half your day there just making your way to the gift shop, keep heading north on 100. You will find the Cabot Cheese place with tons of free samples, then visit the town of Stowe, which is relatively small but scenic and full of good little restaurants and odd shops. Stowe during the summer is relatively empty but most things are still open. It's the exact opposite of the beach community I grew up in...Stowe during ski season is gridlocked and the level of activity resembles downtown in a city. Head a little south to the rotary in Waterbury, go east on Route 2, and encounter some awesome higher-end eateries and breweries. The world-famous Alchemist is out there.
Excellent breweries are all over. Up and down Pine Street in Burlington there are at least a few who do sampling, many offering pub food. Magic Hat is a bit to the south and off Route 7, but still easy to find and close to the city.
If you want good scenic rides to kill an hour or two, I would recommend following Route 15 east/northeast from the "five corners" intersection in Essex, out to the Cambridge area. Also the aforementioned Route 100 from Waterbury to Stowe, and on northward. Interesting shops, people, and land are aplenty.
I could write a book, and I haven't even lived here for long :) I will let others step in.