Sheldons is a small residential community near the Chisholm Elementary School and located close enough to US-1 for access to restaurants, shops, and the things you need without being so close you have to deal with the constant traffic it generates. Having said this, there are plenty of places to eat and shop along the highway and over on the beachside via one of the two causeways running from the mainland to the beachside.
There are a number of parks, preserves, and other places for you and your dog to get out and enjoy the fresh air and sunshine all around you. Some like Pettis Park are small and have just enough space for the two of you to run around in. Others are vast nature preserves with miles of trails to walk on, dense forest canopies to hike under, and plenty of wild animals to be on the lookout for.
As a residential community, the worst of the traffic is likely to be during the morning and evening rush hours. On top of this, you can expect to deal with school buses and children heading to and from school during the school year. Keep in mind that this is a family residential area and the two of you are likely to run across a lot of kids playing nearby while the two of you are out and about walking.
The ground is mostly flat, which may not make for the most challenging walks, but at the same time, it allows you to go as far on your walks as you can. Much of the neighborhood has no sidewalks for the two of you to use. This means being relegated to using the roads. It also means needing to pay extra attention to what's going on around you to avoid tangling with the vehicles on the streets.
The nearest green space is Pettis Park, but it's little more than a couple of tennis courts and basketball courts along with a football field size patch of grass. But it does give both of you a little grass to run around on and stretch your legs.
To the north are several entrances to the Doris Leeper Spruce Creek Preserve. The preserve covers 1,637 acres of dense forests and swamps through which there are a number of trails for you and your pup to explore. If you are feeling particularly energetic, you can hike all the way to Rose Bay and back which is a 6-mile round trip. With such spectacular scenery, this route makes for a great day hike. The best time of day to hike in the preserve is in the early morning hours before the world around you starts heating up and the trails start getting busy.