Pears actually ripen best once they are removed from the tree, and are usually picked before they reach their peak ripeness.
Keep pears at room temperature for best flavor and even ripening. If you want to keep them a few days longer, store them in the refrigerator.
How to know when pears are ripe:
Check the neck! Apply gentle thumb pressure near the neck, or stem end. If it yields slightly, it's ripe!