I organise dance parties in Jordan (e.g. for the Millenium, see the Jordan page on the website) and did my Arabic degree there. It is well worth touring the country, especially Wadi Rum, Petra, Wadi Dana (if you like trekking), Kerak (Crusader Castle) and Jerash (well preserved Roman city) the people are some of the friendliest in the Middle East.
As to diving the Royal Diving Centre, out of Aqaba towards the Saudi border, it's just past the port, is excellent, it used to be run by quite an arrogant English couple but I hear they have fortunately been replaced, all of the 5* offer diving and instructors and the small budget hotels (I use the Red Sea hotel behind the market area as it is cheap and cheerful) will also be able to put you in touch with local operators.
As to the diving itself I can't really help, from what I have heard the better reefs are off the coast so require a boat, but I only started diving in earnest since arriving in Saudi 10 months ago.
Enjoy and good luck.