Modifying a Web Site to Run in VWD 2010 Express .NET 4.0.

 VWD 2010 Express.  Visual Basic.
I have a web site that I developed under VWD 2008 Express (.NET 3.5).  I want to now use VWD 2010 Express for development and use .NET 4.  I surmised that I needed to make some changes in my web.config file to ensure that I use .NET 4 stuff.  So being the simple person I am, I went through and changed ever 3.5.0.0 to 4.0.0.0 such as in the following sections of the web.config.  Did I do the right thing?  The more general question is, "How do I convert a .NET 2.0 or 3.5 to run in a .NET 4.0 environment???
<configSections> <sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"> <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Ex ...