I have been asked several times about removing some of the templates that are available at site creation. There are several reasons you might want to do this and it really is simple to implement.
To hide a template from users, open the Webtemp.xml file located in the
BTW, don't even think about editing anything other than the Hidden parameter in the Webtemp.xml file. You don't want to fall into the unsupported configuration category as KB 898631 explains.