Address the impact that Franklin D. Roosevelt had on the American people after becoming president?

The main impact that FDR had on the people was to give them some amount of hope.  The Great Depression had caused many Americans to lose hope and it was FDR's attitude and his new programs that led them to be more hopeful.

FDR's programs did not end the Depression, though.  They made things better, but did not actually end it.  The Depression would not end until the US started gearing up for WWII.

So FDR's major impact was to make people less pessimistic about their lives and about the nation's prospects.