h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Fermat's marginal note as it is known was written in his copy of Diophantus' Arithmetica, and not one of Euclid's books as you so put it!
in fact Euclid only ever produced one book (Elements) so you wouldn't have many to pick from.
Also you failed to mention that the 'Nova' episode (originally produced by Simon Singh for BBC's Horizon series, who also wrote an interesting novel on Fermat's Last Theorem) was made in 1996 and did point out that Wiles eventually sorted out the error and has sinced produced the proof which is under discussion to be proved. It is not for you or me to judge this and say it is correct or not, but rather that we let time take its course and see if anyone can disprove it (although there are only 6 people in the world who can actually understand it - one of them being Andrew Wiles). Actually I have a rather interesting proof, which this email has not the room for!