Firstly, ASP 2.0 (bundled with IIS4 in 1997) is now completely obsolete -
for ASP Classic questions such as this, please post in:
microsoft.public.inetserver.asp.general

However, to get ASP 2.0 to launch a .NET app, you'll need to make sure that
the appropriate verision of the .NET Framework is installed on the webserver
on which IIS4 is running, and then use the Shell command - something like
(from memory):

<%
Set WSShell = Server.CreateObject("WScript.Shell")
WSShell.Run Server.MapPath("Program.exe")
Set WSShell = Nothing
%>