You can hide this particular link from all but those users with full control over a WSS site rather easily.
- Open the site master page in SharePoint Designer and find the SPSecurityTrimmedControl element.
- The PermissionsString attribute of the SPSecurityTrimmedControl element determines what users can view this content. Change the value of this attribute to ManageWeb and only those users with rights to perform all admin tasks on the site will then be able to see the link on all pages in the site.
- Save and reload!