1) "Lingo". It's a Chuck Woolery game show, but it's all about letters and numbers. The kid loves the letters. He can't guess the words himself yet but encourages mommy and daddy to "Guess it! Guess it!" Note as well that "Wheel of Fortune" is also good.
2) This Old House. This one is obvious if you think it through--construction equipment, construction workers, buildings. What's not to like? He even knows the characters.
We try and limit the TV, and he's usually either reading books or playing with trains when he is watching these shows, but we figure it's better than a lot of things.
