I think ritual without remembering why you do it, or doing it for the wrong reasons is pretty meaningless - a passage from (lol, again) 1 Corinthians in the New Testament comes to mind:
If I speak in the tongues of men and of angels, but have not love, I am only a resounding gong or a clanging cymbal. If I have the gift of prophecy and can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but have not love, I am nothing. If I give all I possess to the poor and surrender my body to the flames, but have not love, I gain nothing.
(that's from the NIV translation btw)

But sometimes ritual can remind us of things, like taking communion reminds us of the sacrifice Jesus made, and I'm guessing many of the Jewish holy days fulfil the same purpose, so that people can remember things God has done.

I think the bible does make it fairly clear that God is more interested in the state of our heart than the outward things we do though.