Editing points in Powerpoint 2010

[PEAB]

Hi, I have just joined this forum and need some help as I have just upgraded from Office 2000 to Office 2010 (home premium version). In the old version, when I right clicked on the shape outline a menu box popped up allowing me to make a curved or straight line on my shape. Now, when I right click the line, the only thing that happens is a new point is added to the line and no menu box pops up. Can anyone tell me how I change a straight line to a curved line in the 2010 version of Powerpoint as I am finding it very frustrating to work with the new version of Powerpoint.