I can definitely recommend several of the suggestions above.
Castleton in the Peak District: I stayed in Castleton earlier this year for 5 nights and really liked my stay there. The village is perfect in that it's quite small, so easy to drive in and drive out of, yet large enough so that it has quite a few good hotels and pubs with rooms to let, and many good restaurants and cafes. It's in a good spot for hiking—in fact, I had a breathtaking view of Winnats Pass from my window, and there are a lot of hikers who stay there. You also have access to the Blue John caves and mines, which are nearby. I found it convenient to get to all my destinations in The Peak, although the area really isn't that large, so pretty much anyplace you stay will be fairly near most sights. One my favorite sights was Winnats Path, a limestone gorge with very steep cliffs and a narrow valley, that is easily hikeable. As you drive through the pass, you are surrounded by towering limestone walls covered with green that rise dramatically on either side of you.
Grassington in the Yorkshire Dales: I did not stay here but did visit and it is a lovely village and fits your needs. If you are a fan of the newest version of "All Creatures Great and Small" it would probably be ideal as the scenes are usually shot here. If you're not, it might be a drawback as it does get a lot of visitors because of that. But it's really a charming place and I don't think you could go wrong here.
Helmsley, North York Moors: I stayed at Foxglove Cottage (Laskill Grange), which would probably be a bit more isolated than what you are looking for; however Helmsley would be ideal, I think. The town is small, but has a number of good restaurants, cafes and shops. Rievaulx Abbey is just a couple of miles away (easily reached along a lovely footpath), as are a number of other sites in North Yorkshire. Thirsk is about 30 minutes away by car. The surrounding area has some of the prettiest scenery I've ever seen, with beautiful green rolling hills, forests, streams, bridges, and lots of wildlife, like pheasants and grouse. I loved it here!
Mousehole in Cornwall: This was another place I went on a day trip, but really enjoyed. It was so charming and cute and I just fell in love with it. It sits right on the sea with a large harbor, some very nice shops and access to great walks along the coast and visits to other sights in Cornwall.