We are from Washington State and are thinking of planning a trip to Boston and then either the Cape, Nantucket or Martha's Vineyard but aren't sure which would be best. We have a 7 and 4 1/2 year old. We want to ride bikes, play at the beach, eat good food. We enjoy being around other families. Coming from so far away this might be our only trip out there and we want to make sure we have that quintessential experience. Does anyone have suggestions as to which place is best or can you describe the main differences between the feel of the places? Thank you!