Here is a chart of the Dow Jones from January 2001, when Bush took office, through today. Click on chart to enlarge.
The facts show that under Bush, the Dow Jones Industrial Average lingered around the 10,000 mark between 2001 and 2006, with a substantial dip in 2002 and 2003. We started two wars then. It then climbed to a peak of 14,000. In 2008, it crashed down almost in free fall. Since Obama took office, it has been climbing steadily.
Here is an updated look posted in January 2015, prompted by a reader.