Sorry to hear that, but you shouldn't mark the thread solved.
1. Apache does not conflict with mysql. Apache, or better a web page can connect to a mysql server to retrieve data
2. Comment out the "LoadModule ..." directive to see if apache complains about the XBitHack directive. Because the way it works now is like it doesn't use mod_include.
Also since you use this directive, create a .html page containing a SSI command (printenv is fine), make it executable:
chmod +x /var/www/html/ssi.html
and see if XBitHack works. Do this before disabling mod_include.
3. My experience with SELinux is very limited, so I cannot be of help here.