FDR created the modern economy

While it is probably true that FDR's policies (referred to as the New Deal) prolonged the Great Depression, many of the programs he created benefited future economies.  In fact, one might argue that some of the programs created by him prevented any future Great Depressions.

The best part about the New Deal, however, was that it dealt with the two main problems that plagued Warren G. Harding and Calvin Coolidge, and that was lack of regulations to deal with greedy cooks, and insurance programs to insure invested money.*

There were laws that existed prior to FDR, yet most of his predecessors believed it was not the role of government to enforce them.  FDR changed this by creating organizations to act as monitors to assure regulations were being enforced.

For instance, the New Deal created the:

• Federal Deposit Insurance Program (FDIC) which insured money invested in banks up to $100,000.  
• Securities and Exchange Commission (SEC) to regulate the stock market
• Social Security Board (SSB) was created by the Social Security Act of 1935 was responsible for monitoring insurance to the elderly, unemployment compensation, and  public assistance. The agency is now called the Social Security Administration (SSA).
• Federal Communication Commission to monitor radio and television
• Federal Housing Administration (FHA) was created as part of the Federal Housing Act of 1934 to set standards for construction of homes and to ensure loans made by banks and other lenders for the purpose of building homes.  It is now called Housing and Urban Development (HUD). This assured that even the poorest people could afford a mortgage on a house. 
• Codes for fair competition were created as part of the National Industrial Recovery Act of 1933
  including production restrictions, minimum wages, and working conditions in order to limit competition and foster a spirit of teamwork among industry rivals.

While these programs were inherently beneficial to the nation, in order to pay for them he had to push tax hikes through Congress, which ultimately tripled the tax rate during FDRs terms in office, raising the top income tax rate to 90 percent.

*By saying greedy crooks, I am not referring to people who are rich, as liberals do.  I'm referring to people who actually violate the law for their own personal gain.