IIS 5.1 Default Website stopped after installing .net framework

I have .NET 4.0 installed along with .NET 2.0. When I used Open Website from VS2010 and tried to run using localhost, the operation failed saying VS was unable to set the mode to 2.0 and it will require manual efforts. I went ahead and in INETMGR I changed the ASP.NET configuration开发者_运维百科 to 2.0.

After this the Default website stopped and even after restarting the IIS service - it didn't connect. I keep on getting the error message "Service didn't response in a timely manner"

Got a solution for this. I saw that my Worldwide Web Service was not running. I started it and the default website started working...