Toddlers are exploring the world and learning new things as they investigate. Give your toddler a balance of things she knows about and things she hasn't learned yet. You will soon discover how fast she learns to master new features and can then decide how often to introduce something new.
Elmo is a long time favorite. Toddler boys and girls adore just about any of the characters in his troupe. These are the favorites. Be sure to check for small parts on each item.