I really like the Park Royal. It's an older property, all-inclusive. It's listed as 'across from beach' but has an underpass to a nice little cove. The price is very reasonable too.
As for a dive shop, we used Scuba Shack. We were able to walk there. Go through the underpass, and across the beach-heading North. You will find Aquaworld, which I don't care for because of the large amount of divers per boat. Next door to Aquaworld is the Scuba Shack. When we were there, we got one free shore dive for every boat dive we booked. We were able to see the Cesna plane wreck, shore diving. Very cool. They had lockers there,(free) which was really nice, as we didn't have to lug our gear with us everytime. Highly recommened! Both the dive shop & hotel. Watch out for the timeshare people at the hotel. They sit in the lobbies & have shirts on that say Royal-so we thought they were hotel employees. Lost 2 hours of vacation time, but did get a rental car for $10