To get your home page to automatically load when the user does not specify a page name in the url, name your home page one of the following:

index.html
index.htm
default.htm
default.asp
index.asp
default.php
index.php
default.html
default.aspx
index.aspx
home.asp
_holding.htm

If a page name is not specified in the url (i.e. http://www.yourdomain.com/) then the server searches for the file names listed above in the order of the list above. The server will display the first page that it finds in the list.  If no page in the list is found, then one of the  pages listed below will be shown:

Coming Soon (_holding.htm)
or
Directory Listing Denied
or
This Virtual Directory does not allow contents to be listed
or
HTTP Error 403 - Forbidden