Explain the difference between Jefferson's and Hamilton's attitudes towards popular participation in the decision making process.

Hamilton and Jefferson offered vastly different perspectives on their vision for what the United States should be. Indeed, Hamilton tended to align more with the upper classes, and wished for America to advance in its financial and economic growth. He was also a strong believer in Federal Power, and the supremacy of the Federal Government over the States. He tended to distrust the ability of commoners to advance their own best interests, an attitude quite common to the Enlightenment.
Jefferson, by contrast, had a much more positive view of the average citizen. He was a supporter of states rights and of limited government, and tended to distrust the elites that Hamilton associated with, and heavily contested Hamilton's federalist and centralizing program.
Even so, I want to stress that even while Jefferson supported the interests of commoners and small government, he also came out of the Enlightenment, and this still implies certain values and ideals, in favor of rationality and education, which tended to be accompanied by an intellectual elitism. Even as he advocated for a decentralized, more localized approach to politics and governance, these Enlightenment era prejudices remained, and he would have balked at the thought of giving the average citizen the ability to wield real political power.