It's a fair old trek from Lahinch to Dingle, it will take best part of a day to get there. Even using the "major roads" some of the minor roads are so minor they're infants. I would estimate approx 4 hours to Dingle, if not more. Ther's plenty to see and do from Lahinch, mostly to the north, however note that Doolin can be as busy as Blackpool especially at Weekends. Ennis the nearest town in a beautiful place. Visit the Friary, the carvings on the McMahon graves are superb You'll have a great time and don't worry about your parents I'm in my late forties too, and can still get around without my Zimmer!