Disabling Smart Scopes in Ubuntu 13.10

To disable smart scopes in Ubuntu 13.10, go to Settings, Security and Privacy, Search, and flip the switch for the setting Include online search results.

To disable specific scopes, go to the Applications scope (Windows/Super key + A), go to the Dash Plugins section and click on See more results. Click on the scope you want to disable and click the Disable button.

For more tweaks that you can do to your Ubuntu 13.10 setup, take a look at:
http://www.noobslab.com/2013/10/tweaksthings-to-do-after-install-of.html