DGS
We went to OBX a couple years ago (2 adults, a 20-something niece, and 3 kids) and had a blast. We stayed north of "the bridge" in Southern Shores. If you want to be within walking distance of stuff, you'd be better off around Kill Devil Hills, although there is some stuff in Corolla/Duck if you want to go that way. We went in early June, which was much cheaper. It gets more expensive as you get into the heart of the summer.
Mike G
OBX is a lotta fun. Eating, drinking, shopping, kite baording, fishing, biking....
You can get a huge 3-4 story house w/ an elevator, pool, hot tub, gym, pool table, home theater, etc. for really cheap during the off-season (like October).
You can also choose the bay side or the beach side; the sun sets on the bay side.