The pant should overlap the shin pads by only by 1 or 2 inches for the best fit. The lower legs should be fully covered but make sure the pad doesn't extend too long . Wear socks that would normally be worn with the skate and slide your foot in all the way to the toe of the skate. If red areas or discomfort develop on the foot, recheck to see if the skate fits properly. Check the blade frequently for chips and cracks and always have a professional sharpen the skate.
Individual choice is the key, but wood is heavier, least expensive and breaks easier.
Aluminum is durable, cost more than wood and can bend. To measure proper length, stand without your skates with the stick straight in between. Mark the stick where it touches your nose and this is where a professional should cut the shaft. To double check, put on your skates and hold the stick in the same position. The mark should now come to your chin or below instead of your nose.