Philosophers perhaps think of Anselm primarily as the author of the ontological argument for the existence of God. But he also authored a number of other arguments for the existence of God, based on cosmological and teleological grounds.
Western theologians however, regard Anselm is important because he interprets the death and resurrection of Christ as the self-satisfaction of God in order to allow for the salvation of sinful men and women whose salvation would otherwise offend God's inherent property of justice. In this way Anselm established one of the most prominent atonement theories in the history of western theology.
Major Works:
St. Anselm at the Christian Classics Ethereal Library: http://www.ccel.org/a/anselm/\n