hm -- us is right: It was nice to re-read this thread.
As hm noted earlier in the thread, those of us who have an acquaintance with the specific field in which Heilsgeschichte would appear would also understand "salvation history", "history of salvation", or even "salvific history" as a technical term (and one that has essentially fossilized). For the general public reading a description of the decorations inside a church, especially from a non-theological perspective, "story of salvation" or "story of redemption" is (probably) better.
As w pointed out in #1, the story of redemption begins with the Fall: Genesis 3:15 is called the "Proto-evangelium" (also "Protevangelium", "Protoevangelium" and "Protoevanglion"). Thus, it would not be out of place for the pictures to include a great many scenes from the Old Testament, particularly those that represent or foreshadow acts of redemption of God's people, e.g. the clothing of Adam and Eve, the Exodus, crossing the Jordan, the Tabernacle, the tree of Jesse, the Return from Babylon.