I'll second the recommendations for Castle in the Clouds and Weirs Beach. Funspot is great, and there's also a drive-in movie theatre at Weirs Beach if you're into that. Meredith is also a nice town for eating and walking around.
Center Sandwich is a great little picturesque New England village, and if you drive a bit farther west on 113 towards Holderness, there's a a nice hiking trail up to Mt. Rattlesnake. It's a short, very easy hike and the views of Squam Lake (featured in the film "On Golden Pond") are well worth it. Also along 113 is Longhaul Farm, an organic farm with great food for sale, among other things.
For the best scenery, go a bit further north to the Kancamagus Highway (112 between Conway and Lincoln), and also to Franconia Notch along I-93 north of Lincoln. The Flume is a cool place to visit, and there's also a short but rewarding hike up Artists' Bluff across from the Cannon Mountain ski area, which gives you a nice view of Franconia Notch (also, you can take the gondola up to the top of Cannon).
There's also a nice hike along the Pemigewassett River that you can access from the exit for the Basin; it's a lot of fun to just take off your shoes and hike in the river (if the water's not too strong of course). You can find similar hikes and swimming holes in the eastern branch of the Pemi along the Kancamagus. You might also consider Loon Mountain in Lincoln, which has a gondola to the summit and various summer activities up there, including some neat caves.
The best views, however, are from the top of Mount Washington (not to be confused with the boat of the same name that services Lake Winnepesaukee). The Mt. Washington Auto Road is off Rte. 16 north of Jackson. The drive up to the highest peak in the northeast is well worth it on a clear day. Just dress warmly - it's pretty typical for the summit to be about 30 degrees cooler than the ground below.
If you're thinking about Maine, the most beautiful areas are located in the Mid-Coast and Downeast regions (east of Bath, esp. Wiscasset, Boothbay, Pemaquid Point, Camden, Acadia, etc.), but if these places are too far for you, I'd at least suggest Cape Neddick and Cape Elizabeth to see the lighthouses, and perhaps Old Orchard for a lively beach town if you're in the mood (of course the ocean water is a bit cold

). You could also go canoeing or kayaking in the Saco River, which is lots of fun.
Ok, hope that information wasn't too overwhelming
