Of all time...
#1. Herbert Hoover
#1. Franklin Delano Roosevelt
#1. Obama.
What did Herbert Hoover do that W. Bush didn't do? I guess you could lay the Smoot-Hawley Tariff on Hoover (or "Hoot-Smalley", as Michele Bachmann says
), but then you have to lay the unfunded, nation building war in Iraq on W. Bush. Both allowed or supported actions and policies that led us into severe depressions/recessions though. So I put them ahead of anybody else.
But if you want to go back as far as Hoover, I'd put Hoover at #1, W. Bush at a close #2 and Warren G. Harding at #3... tied with Nixon (the Corruption Twins). Thus far, I'd put Obama somewhere in the middle, along with Bush I, Truman and Eisenhower.
People like you answer based solely on ideology. But as far as effectiveness and what they've done for (or to) the country, those are my answers, political ideology aside. Leading the nation into depressions/recessions easily gets your name near the top of the list, in my book.
P.S. Since you put "Of All Time" as your header, that tells me a lot about your knowledge (or lack thereof) of American history. Andrew Johnson, anyone?