How to pick a good Study Bible

Open Study Bible: First published in 1975 and the expanded editions in 1983, 1985, and 1990. This Study Bible is very popular among evangelicals of most denominations. This study is Objectively Oriented which means this New Open Bible is NOT a commentary but rather it is one of the few Bibles that use the Scriptures themselves to illuminate and clarify the text.

The NKJV Open Bible, Classic Edition is designed for the hungry reader.
This Bible is filled with amazing study aids including:
comprehensive book introductions and outlines,
64-page concordance,
Read-Along references and translation notes,
Classic Biblical Cyclopedic Index covering over 8,000 textual entries.
Seven-step Method on How To Study the Bible,
Visual Survey of the Bible,
The Christian's Guide to New Life
The Greatest Archeological Discoveries of the Bible.
Words of Christ are in Red.

The choice of a Study Bible will probably depend on your theological leanings. The designation "study Bible" can refer to two things. In some contexts it refers to the translation itself, to a version of the Bible suitable for study. More often, however, it refers to a translation plus a set of features designed to help one read and study the text.

Objectively Oriented Study Bibles (accepted by most denominations)
Dickson New Analytical Study Bible
New Open Bible
Thompson Chain-Reference Bible

Subjectively Oriented Study Bibles—Conservative: Dispensational (Accept by specific denominations)
Companion Bible
Ryrie Study Bible
Scofield Reference Bible and New Scofield Reference Bible

Subjectively Oriented Study Bibles—Conservative: Reformed (Accept by specific denominations)
New Geneva Study Bible (Thru 1995) (The first edition of the Bible in English that qualified as a "study Bible" was the Geneva Bible; it contained extensive cross references, synopses, and doctrinal points. The text of the Geneva Bible was never printed without the commentary. The (English) Geneva Bible, first published in 1560, was "provided with marginal notes based on Reformed principles.")

NIV Spirit of the Reformation Study Bible
ESV The Reformation Study Bible (formerly called NEW GENEVA STUDY BIBLE)

Note regarding The Reformation Study Bible:
"The Reformation Study Bible is so called because it stands in the tradition of the original Geneva Bible... The Geneva Bible was published in 1560, carefully designed to be accurate and understandable. It was the first English Bible to use verse divisions, as ‘most profitable for memory’ and for finding and comparing other passages. It was provided with marginal notes based on Reformed principles.

The Geneva bible dominated the English speaking world for a hundred years. It was used by Shakespeare. The King James Bible was published in 1611 but did not supplant the Geneva Bible until Fifty years later. The Pilgrims and Puritans carried the Geneva Bible to the shores of the New World. American colonists were reared on the Geneva Bible. They read it, studied it, and sought to live by its light.

Since that time a multitude of English translations and study Bibles have appeared. None of these study Bibles has incorporated a summary of Reformed theology. The Reformation Study Bible contains a modern restatement of Reformation truth in its comments and theological notes. Its purpose is to present the light of the Reformation afresh."

The contributors to this volume, then, are largely teachers at seminaries of Calvinist persuasion. Names as JI Packer and Simon Kistemaker appear amongst the contributors. Eleven of the contributors come from Westminster Theological Seminary (be it the Philadelphia or the California branch). Nine others come from the Reformed Theological Seminary in Jacksonville, USA.

Conservative: Evangelical (Accepted by Most Denominations)
Disciple's Study Bible
Harper Study Bible
Hebrew-Greek Key Study Bible
Life Application Bible
New Student Bible
NIV Study Bible
The Quest Study Bible
Word in Life Study Bible

Conservative: Pentecostal / Charismatic
Dake’s Annotated Reference Bible
Full Life Study Bible
Spirit-Filled Life Bible
The Word Study Bible

Conservative: Wesleyan / Holiness
The Wesley Bible

Non-conservative: Mainline Protestant
Cambridge Annotated Study Bible
HarperCollins Study Bible
New Oxford Annotated Bible
Oxford Study Bible