Part of what made the Great Depression so bad was the wide spread criminal actions of those on Wall Street. Companies pooling together to "trade" stocks at artificially high prices so as to drive the prices even higher. Then average Joes were able to see all the "fortunes" being made on Wall Street, at which point they would invest all of their money in stocks. Once the actual price of the stock became known huge sell offs would occur. Banks were doing the same thing with money they didn't have so when they lost it, they didn't have any to give to their customers when they showed up to make a withdrawl.
When the panic set in President Hoover was advised that the market is fluid, it had dipped before and recovered, why shouldn't it this time? Hoover said what the public wanted to hear, that everything was okay and would be better by morning. By the time he agreed to try anything to help it was too late.
I agree with the average history minded American that FDR was a great president (even if he was a PHRASECENSOREDPOSTERSHOULDKNOWBETTER....j/k), his technique of try everything to fix the problem until you find something that works is all he was left with once he was elected. Let's not forget however that a HUGE part of what brought the U.S. out of the Depression was World War II. The massive wartime production of goods the U.S. put out into the world economy was the biggest single fix of the Great Depression, but at a horrible cost. An economic boom on that scale is highly unlikely at this point in history.