RE: Is Skeet Shooting good practice?
Like has been said above, any practice will help, but I would say sporting clays would be most like duck or goose hunting. In trap ALL the targets are moving away from you, in skeet they are relatively close, which is usually not the case in hunting waterfowl. Depending on the course, at least in sporting clays you're likely to get longer shots with different elevations. A lot of clays courses have shots that are in no way realistic in the hunting world, but it's definitely the most realistic of the bunch when it comes to waterfowl. 5-stand would be next because there are a variety of shots (compared to trap and skeet).
One other consideration: sporting clays is usually a bit more expensive than skeet or trap ($20/100 versus $12/100 at my club), due to the larger number of target-throwing machines required. If you're starting out, you might want to spend your money on skeet or trap until you are consistently busting targets before hitting the sporting course.