This is from my httpd.conf. I have commented out the default location they chose and changed it to a more genearl /var/www/html
Make this change yourself (to wherever you want your web root), stop and start apache.
# DocumentRoot: The directory out of which you will serve your
# documents. By default, all requests are taken from this directory, but
# symbolic links and aliases may be used to point to other locations.
getenv("DOCUMENT_ROOT") also works for me, without having to worry about register_globals ...