A bare-minimum example of how to work with an LCD Keypad Shield from DF Robot for Arduino.

Arduino-LCD-Keypad-Example.ino

/*
 *  Basic example code for working with an LCD Keypad Shield 
 *  from DF Robot and an Arduino Uno.
 *  Written by: Konstantin Farrell
 */
#include <LiquidCrystal.h>

LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

int readkey;

void setup() {
  lcd.begin(16, 2);
}
void loop() {
  lcd.setCursor(0, 1);
  readkey=analogRead(0);
  if (readkey==0) {
    lcd.clear();
    lcd.print("Button Right");
  }
  else if(readkey==98) {
    lcd.clear();
    lcd.print("Button Up");
  }
  else if(readkey==254) {
    lcd.clear();
    lcd.print("Button Down");
  }
  else if(readkey==407) {
    lcd.clear();
    lcd.print("Button Left");
  } 
  else if(readkey==637) {
    lcd.clear();
    lcd.print("Button Select");
  }
}