The Brahma Sutra is the Vedanta Sutra - they are one and the same thing. From my experience, one would benefit greatly from some commentary, as the meaning is very diffficult for one not well versed in many aspects of Indian philosophy to discern. The text is like a series of brief aphorisms, written in a very minimalist style. There are many other Shastras which are easier to understand.
The Brahma Sutras were composed as a commentary on the vedas and upanishads - capturing the essence of the upanishads. A very very good commentary by Swami Sivananda is available online at http://www.swami-krishnananda.org/bs_2/bs_2-1-12.html.
