Either a sutta anthology like Bodhi's "In The Buddha's Words", or Thanissaro's "Wings To Awakening"... or one of those classic Theravada introductions like Walpola Rahula's "What The Buddha Taught" or Narada's "The Buddha & His Teachings".
Alternatively, if approaching it from a meditation perspective, I'd concur with Ben's recommendation.
"Do not force others, including children, by any means whatsoever, to adopt your views, whether by authority, threat, money, propaganda, or even education." - Ven. Thich Nhat Hanh
"The uprooting of identity is seen by the noble ones as pleasurable; but this contradicts what the whole world sees." (Snp 3.12)
"To argue with a person who has renounced the use of reason is like administering medicine to the dead" - Thomas Paine