So I think this discussion did not hit the point exactly. While I agree with almost all statements that were made, such as Turn the wheels when parked on a hill,..
I would like to add that for long term parking, such as winterizing a car or anytime you leave your car parked for several month, I would suggest turning the wheel into the straight ahead position. The reasoning behind that logic can easily be learned when reading up on alignments for Drifting cars. The reason why drift cars have such an extreme negative camber is so that when they are turning their wheels full lock, they will return to a 0 degree camber and have the maximum amount of contact/grip on the road.
In short, When the front wheels are turned all the way to one side, the camber increases due to the positive caster that most cars have. Thus if you park with your wheels fully turned to one side, the weight of the car will mostly sit on the outer side of the tire rather than evenly distributed on the entire contact patch of the front wheels. That being said, parking with your wheels turned, will put a bit more strain on your suspension, wheel and tires, but this is nothing that you should worry about too much.
In Conclusion, straightening your wheels while parked is preferable, but not vital for the health of your car.
FYI, if you want a more detailed explanation of the logic i use, you can watch this video
While we appreciate the information provided, I feel inclined to lock this thread due to the musty smell from it being un-used for 10 years.
Feel free to start a new discussion.
~DaTT