We have been to St. John many times and love it. Really, all the beaches are beautiful, so it’s just a question of what sort of atmosphere you’re looking for.
In terms of car rentals, most people recommend getting a 4-wheel drive, but from the Westin you can easily use taxis (or get a normal rental). If you plan to spend time on the south and southeast side of the island, where there are no paved roads, a 4-wheel drive is better.
Every morning, check the weather report and see where the winds are blowing. There’s always a lee side of the island, and that’s where you want to snorkel that day. If you’re looking for a calm snorkel, Salt Pond, on the southeast corner, is protected from almost all sides and is rarely crowded.
Trunk Bay is indeed really touristy, but it does have a neat underwater snorkel trail. If you want to go there, first thing in the morning is best, but be prepared for crowds to inundate you quickly.
As mentioned, Waterlemon Cay is a great spot. There’s a small island you can snorkel around, provided you are strong swimmers. The waves on the ocean side can be quite strong.
Little Maho Bay is fantastic. There’s no parking lot, just pull off on the side of the road.
If you like to kayak, there’s a good kayak/watersports outfitter in Coral Bay called Crabby’s. You can rent kayaks and paddle across Coral Bay to the east side, where you can snorkel on a completely empty beach.
A final point about snorkeling and beaches: Caneel Bay resort is private, but the beaches are open to the public. There are seven of them, several of which are very nice. Take advantage of these.
As for food, two of our favorites are Miss Lucy’s, which is south of Coral Bay, and has very good local food and a beautiful view (one of the very few places right on the beach), and Aunt Vie’s, a tiny roadside shack serving the best conch fritters on the island. As a bonus, it is located in the east end, a very fun ride and far from most tourists. You can get delicious, if overpriced, smoothies from a truck half-buried on the side of the road at the intersection of Rts. 10 & 20 on the way to Coral Bay. For a romantic night out, try Asolare, on the hill north of Cruz Bay.
Vix and SuaSponte