Scott Schecter comes to my rescue. We are working on a DNN site that needed the radio buttons turned off. Here is his link discussing how to turn off the search radio buttons for DotNetNuke 4.5.2 (and above).

It is a setting in the .ascx skin file. Add the two attributes in red as shown below for the dnn:SEARCH element.

<dnn:SEARCH runat="server" id="dnnSEARCH" showWeb="False" showSite="False" />