I'm sorry about how simple the question is but I've searched all over the Internet and I found MSDN articles about making application pools (http://msdn.microsoft.com/en-us/library/ms525309.aspx) and using IIS 7 but nothing about IIS 6 and applications.
I'm currently using the following code to create an application and set its properties:
Set oWebAdmin = GetObject("winmgmts:root\WebAdministration")
' Define the Path, SiteName, and PhysicalPath for the new application.
strApplicationPath = "/B2"
strSiteName = "Default Web Site"
strPhysicalPath = "C:\inetpub\wwwroot"
' Create the new application
oWebAdmin.Get("Application").Create "/B2", "Default Web Site", "C:\Inetpub\wwwroot\B2"
Set app = oWebAdmin.Get("Application.SiteName='Default Web Site',Path='/B2'")
app.AuthFlags = 21
app.NTAuthentication="yourfriendlydomain.helloworld.com"
However, I get 0x8004100E (Namespace specified cannot be found.) and I haven't got the faintest idea how to proceed.