• Click on the “Customize” tab of Sense.
  • In the lower right corner of the screen, click “Menu” and in the dropdown menu, select “All options”.
  • Click on the icon “first screen” (for WM 6.5) or go to the tab “Personal” and click on the “Today” (for WM 6.1).
  • Under the “Items” tab, select “Windows default” instead of HTC Sense (for WM 6.5) or remove the box “TouchFlo 3D” (for WM 6.1).
  • Click OK.

If not working try these steps :

Start -> Settings -> Right Softkey -> More.. -> Today -> Items and choose Windows Default.