Assets->Import Settings??where is it ?

URL http://unity3d.com/support/documentation/Components/wizard-RagdollWizard.html

"When you've created you character and rigged it, save the asset normally in your Project Folder. When you switch to Unity, you'll see the character asset file. Select that file and choose Assets->Import Settings... from the menu bar. In the Import Settings dialog, make sure that Generate Meshes is not enabled. "

where is the " Assets->Import Settings"???i use the version 3.1 pro for windows

It hasn't ever existed on Windows, and no longer does on OS X either. Just click on the asset in the Project pane, and then look at the Inspector pane.