Donna,
I will give you my answer (with no guarantee that it is the correct one). To check which version of .NET I was running, I looked in the install/uninstall programs control panel. There I saw .NET 2, 3, and 3.5, with various service packs. I figured if it wasn't uninstalling with prior automatic updates, I would just do the same and add the new one.
I suppose that goes along with John's info, which to me suggests that certain applications may still need the older versions of .NET to properly function.
