ACZoom

In my opinion, the best hot dogs have a snap to them, are grilled, and are not skinless.

Nathan's in Coney Island claims to be very good, and it is.
Take the subway to Stillwell Ave/Coney Island, and it is across the street.

But I would not recommend it - everyone seems to want to eat here, and even with multiple lines, and only ten people per line, it takes over 30 minutes to get to the front and get a hot dog.
Not worth it - especially since most of the hot-dogs sold by all vendors are actually made in one or two places only - Sabrett is the main one in New York.

Gregory and Paul's, also at Coney Island, is a better choice - great taste, and no waiting. There are two of them - one on the boardwalk, and the other one across from the Cyclone roller-coaster ride.

French Fries are a different matter - it is important to eat fries that are no more than a minute or two off the fryers. So, look for a place that is crowded - that way you know the fries will not be stale - even five minutes is no good for fries. So, Nathan's always has the best fries, at the other places, it depends.