No doubt about it its a 5 hour drive. I have done it many times to see my family that lives in Kitty Hawk. I take 17N all the way to 64 and then take that over to the beach. I agree with taking the ferry from Cedar Island to Ocracoke, and Ocracoke to Hatteras and then driving up the rest of the way. That can take 8 hours+ but going that way is stressless and there is lots and lots to see. Check out
NCDOT: PDF Document
If you want to show them the NC Coast, there is no better way!