A transcript of his entire speech can be found here.
The most controversial parts of his speech that caused dismay among Westerners were his criticisms of Israel and the US' involvement in Iraq and Afghanistan.
Here's an excerpt:
How can one imagine that the inhuman policies in Palestine may continue; to force the entire population of a country out of their homeland for more than 60 years by resorting to force and coercion; to attack them with all types of arms and even prohibited weapons; to deny them of their legitimate right of self-defense, while much to the chagrin of the international community calling the occupiers as the peacelovers, and portraying the victims as terrorists. How can the crimes of the occupiers against defenseless women and children and destruction of their homes, farms, hospitals and schools be supported unconditionally by certain governments, and at the same time, the oppressed men and women be subject to genocide and heaviest economic blockade being denied of their basic needs, food, water and medicine.Apart from the last part - which refers to the conspiracy that Jews rule the world - I really don't see the issue here. What has happened/is happening to the Palestinians can't be disputed. I don't think the Palestinian spokespeople, or even Iran's major rival in the region in Saudi Arabia, would argue the case differently.
They are not even allowed to rebuild their homes which were destroyed during the 22-day barbaric attacks by the Zionist regime while the winter is approaching. Whereas the aggressors and their supporters deceitfully continue their rhetoric in defense of human rights in order to put others under pressure. It is no longer acceptable that a small minority would dominate the politics, economy and culture of major parts of the world by its complicated networks, and establish a new form of slavery, and harm the reputation of other nations, even European nations and the U.S., to attain its racist ambitions.
The German FM labelled Ahmedinijad a disgrace, and that he may be, but what is even more disgraceful is the West's complicity in the suffering of the Palestinian people whilst espousing the grand hypocritical ideals of human rights.
The rhetoric of Ahmedinijad was not unexpected. However, what has differed this speech from previous Ahmedinijad rants at the UN was - as the NY Times noted - the few conciliatory remarks that may pave the way for constructive dialogue with the US. This is what the West should be focusing on, instead of stubbornly walking out of an international forum.
As Mohamad Bazzi highlighted on the Huff Post, Ahmedinijad's rhetoric is aimed at the Arab audience, a means to improve his and Iran's populist stature within the Arab world. Iran has benefited significantly since the Iraq invasion of being the only Islamic power to 'appear' to stand up to Israel and the US, whereas Arab states have grossly failed in this regard.
Having popular Arab support on its side enables Iran to exert greater influence in the Middle East (Syria, Lebanon and Palestine good examples).
Slamming Israel at every opportunity and championing the cause of the Palestinians is the greatest way to mobilise Arab popular support, and Ahmedinijad successfully does it over and over again. A dozen Western delegates may have walked out of the UN chamber, but millions of Arabs will be praising Ahmedinijad tonight.