Ubuntu :: PHP Files Downloading And Not Displaying Page

When I try to load a php file my browser downloads the file instead of displaying the page. Here is my apache conf file.
#
# Based upon the NCSA server configuration files originally by Rob McCool.
# This is the main Apache server configuration file. It contains the configuration directives that give the server its instructions.
# See [URL] for detailed information about the directives.
# Do NOT simply read the instructions in here without understanding what they do. They're here only as hints or reminders. If you are unsure consult the online docs. You have been warned.
# The configuration directives are grouped into three basic sections:
# 1. Directives that control the operation of the Apache server process as a whole (the 'global environment').
# 2. Directives that define the parameters of the 'main' or 'default' server, which responds to requests that aren't handled by a virtual host.
# These directives also provide default values for the settings of all virtual hosts.
# 3. Settings for virtual hosts, which allow Web requests to be sent to different IP addresses or hostnames and have them handled by the same Apache server process.
# Configuration and logfile names: If the filenames you specify for many of the server's control files begin with "/" (or "drive:/" for Win32), the server will use that explicit path. If the filenames do *not* begin with "/", the value of ServerRoot is prepended -- so "/var/log/apache2/foo.log" with ServerRoot set to "" will be interpreted by the
# server as "//var/log/apache2/foo.log".
#