I would like to simply mention that from the afternoon before Tisha B'Av till after Tisha B'Av, Torah related discussions should be ONLY focused on the Destruction of the Beis Hamikdash and similar topics.

Other Torah topics are not to be learnt or studied.

There are many topics that are permitted to study.

Aish Hatora's website for Tisha B'Av: http://www.aish.com/holidays/tisha_bav_and_the_3_weeks/default.asp

From Artscroll:

The classic Torah study for Tishah B'Av study is the series of Talmudic narratives about the destruction of the Second Temple.
Included are narratives of the internal struggle between the leaders of the nation and the instigators of war.
For the benefit of our readers, we present a section of this Talmudic portion (Gittin 55b-56a), adapted from the Schottenstein Edition of Talmud Bavli.
PDF File of the Gemorah in Gittin 55b-56a

The Judaica Press Complete Tanach with Rashi:
Iyov - Job
Eichah - Lamentations