Woah! Well, I couldn't see anything wrong by scanning through your post information. It could be just something simple you've missed, however with all of the changing of configurations, etc... it seems like uninstalling apache/php/phpmyadmin/mysql/xampp/whateverelseyouinstalled and starting over may be a good idea.
I don't know if this will help at all, but I've configured this stuff numerous times on SuSE 10 and I do it pretty much the same way every time; if you follow these steps you shouldn't have to worry about using something like xampp and it may just help fix your issue:
1. Install apache2 through YaST (plus prefork/worker dependencies) -- I usually don't do this from the Network Services --> HTTP Server setup, but just type "apache2" in the yast software management panel to find and install it
2. Make sure you start apache up (/etc/init.d/apache2 start) and then put a simple index.html file in your /srv/www/htdocs directory. Open it in a browser locally (
http://localhost) and see if you can see it. (Remember if you want to access your pages from a machine other than the one you are on you need to enable HTTP traffic in your firewall settings).
3. Install PHP5 and the apache_php5 module (again from YaST software management)
4. If you want, add index.php to your apache conf file (DirectoryIndex index.html index.php index.html.var)
5. Restart apache (/etc/init.d/apache2 restart)
6. Put a simple test.php file (something like <?php phpinfo(); ?>) in your /srv/www/htdocs/ directory.
7. Open up your local browser again (
http://localhost/test.php) and make sure apache serves that page correctly
8. Install mysql through YaST software management and make sure it is running (/etc/init.d/mysql start)
9. Now go to phpmyadmin.net and download the latest phpMyAdmin tar file (I always get it from here because I have had numerous problems trying to install phpMyAdmin from YaST)
10. Install phpMyAdmin (basically untar in your /srv/www/htdocs/ directory and rename to "phpMyAdmin" or whatever you want)
11. Change your phpMyAdmin user and password settings and permissions to get rid of those security warnings
12. Restart apache again and access your localhost/phpMyAdmin page.
Well, that's about it. Once you get to that point I would recommend setting up your virtual hosts, etc...
Hope that helps.