I have used "Baby Einstein" Movies since the day my four year old was born.  As a new born, I played Baby Mozart for him.  It is designed to stimulate the brain by sight and sound.  He loved it, he would lay there on the floor or in his bouncer, just kicking, and smiling, and making all kinds of happy baby sounds. 

I kept buying them as he got older and I was able to use them for my second son also.  And they are still fun for the older kids to watch along side the younger kids.  They offer different learning levels of shapes, colors, music, instruments, animals(farm, water, pets, etc), words,...