1. Yes, it is. You get many features like getting a free bus over there which drops you off right at the entrance, and Extra Magic Hours. Plus some of them arent too expensive.
2. Well for Epcot and Magick Kingdom, it will take about 1 or 2 days, 2 days if you are planning to do every single thing. MGM and Animal Kingdom can take about a day.
3.Well, this I am not quite sure. Try asking an employee at Epcot or something.
4. Well, nothing more other then that.
5. Well depends on your budget. I personally like the French Quarter and Riverside. If you dont want to waist alot of money, hit up the vaule resorts. They can save you alot of money, and they look cool too.
And here is an obvious tip for when your at the parks; make sure you try to go to all the popular attractions in the morning, they are always relativetly empty, like a 0-10 minute wait.