Dartmoor is a wonderful and very atmospheric place and there are many well documented short walks available with refreshment stops. There are opportunities for guided walks and talks about the moor throughout the main season, see http://www.dartmoor-npa.gov.uk/
Three longer trails also take in the moor: Two Moors Coast to Coast (137 miles); West Devon Way (37 miles) and the Templar Way (18 miles). This latter runs between Haytor on the moor and Teignmouth on the coast.
There are many different events in the towns around the moor including a food festival in Moretenhampstead in March, a Contemporary Craft Fair in Bovey Tracey in June, the famous Widecombe Fair in September, and the Tavistock goose fair in October.
Sandays to Bovey Tracey is a drive of just over half an hour and is a good access point to Dartmoor. During the summer season there are usually hopper buses from Newton Abbot,and trains linking Exeter and Okehampton on the Dartmoor Railway, providing some alternatives to driving.