I was there too. The depression lasted from 1929 until at least 1940 (unemployment rate still 17 per cent.), when the build-up to WW2 started industry going again despite Roosevelt's policies. For me, that was from age six to 17. Outside of industry concentrations it lasted longer, but it was at least ten years. Roosevelt's anti-competition stance and widespread price-fixing led to stagnation, even though NIRA was declared unconstitutional.

Would recovery from the current bust be more rapid without government intervention? We can only guess. EU countries, Japan and others besides the U. S. are pouring money into the hole, but the stance is protectionist and probably wasted.

This release from UCLA, Cole (of Penn State) and Ohanian of UCLA, is worth reading. "FDR's Policies prolonged Depression by 7 years, UCLA economists calculate."
http://newsroom.ucla.edu/portal/ucla/FDR-s-Policies-Prolonged-Depression-5409.apx