The basic open water course is a little bit James Bond - when you finish you get a license to kill, but its only valid when used on yourself and/or your buddy.
I kid, but I have a point to make. The 2006 DAN Diving Report has the usual harsh lessons about training, experience, and currency: 45% of diver fatalities in 2005 had fewer than 20 dives in the previous year, 44% had been diving for less than two years, and 40% had minimal or no certification. Fatalities are very rare, but what is more common is for an inexperienced diver to have a panic situation or some other issue due to insifficient experience and then stop diving as a result. Training helps you minimize the bad experiences and handle them more successfully when they arise.
The point I want to make is that being certified will not by itself make you ready to dive. You also need to get yourself into a network (or set of networks) that will help you through your first couple hundred dives. ScubaBoard is one network, and I particularly recommend the Wrinkles beach dives and Mo2vation boat dives. Some of the dive shops also have regular dives. Plan to get much more training after certification and then dive regularly or not at all.
Hope to see you in the water.
Jim