One of the points of the interest in the Aznar-Bush conversation from February 2003, the record of which the White House has not disputed, is the role of Saudi Arabia in general and Prince Bandar in particular as an enabler of the war. Bush was sanguine about any disruption in oil supplies --
"the Saudis would help us and put all the oil necessary into the market,"
which might come as news to the current King Abdullah, who is not especially keen on the invasion. Furthermore, as the same Reuters news article points out, someone from within the Arab world leadership seems to have squelched a proposal from the UAE that would have eased Saddam out of office without a war.
That Saddam and his sons leave Iraq, unconditionally, was the final demand of George Bush before the outbreak of hostilities. Incidentally, Bush's full address from that evening when he issued the ultimatum is useful reading for a variety of reasons, not least because it anchors the purpose of the war solely in WMD. None of the other later goals of the war are mentioned.
Bush's defenders like to go back to his speeches from the pre-war period and find evidence that other goals like democracy promotion and Middle East peace were mentioned. But the core legal basis for the war was WMD. The other goals were an ex post graft that, for instance, did not figure in the British legal basis for going to war in the first place.