I have a 96se Automatic that sometimes has problems after the car is put in the Park position. The lever can only be moved to the other driving gears if you apply some force and you hear a little "grating" sound. It does not matter if the car is parked on level ground or an incline and using the handbrake does not help. Sometime it shifts normally/easily.
Also, is there a fix for the driver's side window rattling when it is only slightly open.

 

dont know about the window but i had the same problem in my altima with it getting stuck in park. the neutral/safety switch had gone bad and i could only start it in neutral then switch to drive because it would not shift from park. if its just hard to switch then try applying the parking brake then switching and see if that makes it any easier. also when i switched to synthetic tranny fluid it was easier to shift out of park no matter what incline it was on.