Hopefully this will help.
The priority for loading index pages on sites is a setting in Apache. Unless set otherwise i believe the load order would be:
DirectoryIndex - index.html index.htm index.shtml index.cgi index.php index.php3 index.pl index.xhtml
Therefore if you wish page 1 to be index.html that should load first, then when that is submitted or a link clicked on you would need to set the link to direct to Page 2 which could be any page... .html or .php ie. if you want dolphin to load on index.php (the homepage), or join.php (the join page), etc..
If this is not what you wanted to achieve, perhaps you could provide some more information and an example of what you are trying to achieve.