<<Can someone tell me why the Church does not recognize the great figures of the Old Testament as saints? Ive noticed that we dont refer to Moses as St. Moses or any other person in that way, im just curious as to why we dont. Also, why do we not ask these same people of the Old Testament to pray for us?>>
Where did you get the idea that the Church does not venerate the righteous of the OT?
The Eastern Churches certainly do.
The Roman Church is unusual in that of all the OT righteous, the only ones liturgically commemorated are the Maccabees on 1 August. Elijah, Elisha, and David are on the Carmelite calendar as well.
And in my city there is a Roman church called Prophet Daniel Catholic Church.