I notice in reading my Bible that the names of the Old Testament books have often been changed to correspond with the Protestant Bible. Any particular reason for this?
Start by realizing that the Bible itself is a collection of writings made over centuries of time. From early on, not all agreed on which writings were inspired and to be placed in what we call the Bible. Those differences were carried over among Christians who would also, in the beginning, differ concerning what books of the Christian era were inspired.
All that led to the Church's action at the Council of Trent in 1546. Trent defined what books were to be taken as inspired and thus included in the canon of Scriptures.Just as differences among language groups over what books were inspired went back to their languages of composition, differences in names and spellings sometimes go back to the languages translators used.
The point is that a lot of hands were involved in shaping modern editions and translations of the Bible.