Menachem Mendel has a nice post collecting a lot of the material on the Ten commandments. However, there is one point that I think is worth discussing.While 10 Commandment displays are ubiquitous in synagogues, it is far from certain this is the correct approach. Specifically, the Talmud records that public recitations of the Ten Commandments are banned because there were those who understood these readings to mean only the Ten Commandments are important to the exclusion of the rest of the Torah. R. Yom Tov Lipman Heller in his commentary Ma'adani Melekh (or Ma'adaani Yom Tov) says this reasoning should apply to Ten Commandment displays and he questions the practice of putting such displays up in synagogues. This statement is quoted in the Ma'gen Avrhom's commentary on the Shulkhan Orakh. Many others question this practice including R. Ahron Lewin, (Reischer Rav) in his commentary on Berkahot.None of this, however, stopped the Agudah, the OU, and Nathan Lewin (R. Ahron Lewin's grandson) from filing a brief in the Supreme Court advocating for Ten Commandment displays. While there is one person who permits such displays - they do so only in the context of a synagogue. That is, because in a synagogue the Ten Commandments would be part of the rest of the ornaments - Torah etc. it is clear that one is not imbuing them with any additional import. But, it is equally clear that the types of displays the Court would allow for - those totally devoid of any other Jewish context would run afoul of the Talmudic injunction.