I often get asked if it's possible to prevent users from editing sites with FrontPage 2003 (for v2/2003) and SharePoint Designer (v3/2007). Yes, this is possible. Unfortunately, you have to do it at a Site Definition level. So, it's either all or nothing for a specific type of site.

How to disable FrontPage 2003 authoring for Windows SharePoint Services 2.0

How to prevent SharePoint Designer 2007 users from changing a Windows SharePoint Services 3.0 site or a SharePoint Server 2007 site