I discovered X-Plane in 1998. I started playing it, but with joystick and pedals. Then, in 2002, I discovered the European Ultralight class, similar perhaps to the American Sport Pilot license.
I started flying with an instructor to get my European Ultralight license and the first he asked me was: "Have you been flying before?" Well, I told him that I had several years flying radio controlled gliders with my son, then the X-Plane simulator experience. He said: "I see that it helps!"
The X-Plane is an excellent simulator. Contrary to the Microsoft Flight Simulator, it is a virtual air tunnel: you have to get the airfoils right to have it behaving correctly. Let me explain:
In MS FS, if you build an aircraft and enter say 60 knots as the stall speed, it will stall at that speed. In X-Plane, you will have to model the airframe, CoG, airfoils, etc. correctly. Then you fly for the first time and if the aicraft stalls at 60 knots then you are very lucky! You'll have to go again in the model, find out what is different from reality and brush it up.
Each surface is an airfoil with its lift, drag and moment. I once modelled the Russian Orlyonok, a WIG seaplane and couldn't get it out of the water. I asked Austin Meyer, the creator of X-Plane, and he said: put the step in the hull a tiny bit more aft. Which I did and ... the Wing In Ground seaplane took off!
But, remember, you must fly with both a joystick and pedals and learn things like, side-slipping. Flying visual is not good in a simulator but you can learn instrument procedures.
In 2002, after getting my license, I bought a Kitfox 3 light aircraft and I have been flying it ever since. I have about 850 hours on it. Been from Norway to Belgium, Germany and - best of all - north of Norway! Flying the Norwegian fjords at 2,500 ft above the water is a mind blowing experience!
Good luck with your aviation future!
PS: Some of my recent flights on YouTube:
http://www.youtube.com/watch?v=tOmgc1OBG5A
http://www.youtube.com/watch?v=b1Xnjl_oh3Q
http://www.youtube.com/watch?v=rcylNG-klDs