How to hide ribbon row when enabling anonymous access in SharePoint 2010
When you enable anonymous access to your site the ribbon row will appear for anonymous users but without "site actions" menu and it will be "Login" link but if you need to hide all this row you have to do the following
1- Open your masterpage with SharePoint designer
2- Find the ribbon row Search on "ribbonrow"
3- before the div that holds the ribbon add this tag
<sharepoint:spsecuritytrimmedcontrol id="SPSecurityTrimmedControl2" runat="server" permissionsstring="ManageSubwebs">
4- after the end of the ribbon div close the security tag