HKEY_CURRENT_USER\Software\SolidWorks\SolidWorks 2005\User Interface\Toolbars
Go to Start, Run, and typoe regedit. Rename the above key in your registry with Solidworks shutdown. Then restart Solidworks, your Task Pane should come back. This basically removes your toolbar setting and they go back to the default. Recently had this happen to me and the above fix worked out great.
Jim