How to get listview click? And back button?

[AlexMason]

I have my files all set up to make my list view and when i click on a item from list view i want it to make an output but everything i found online and tryed makes and Force Close here is my files.

Spoiler

Main Class:

package com.alexmason.mkw;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

public class Main extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final Button btnMarioChar = (Button) findViewById(R.id.BtnMarioChar);
        final Button btnMarioBike = (Button) findViewById(R.id.BtnMarioBike);
        final Button btnMarioKart = (Button) findViewById(R.id.BtnMarioKart);
        final ListView lvMarioChar = (ListView) findViewById(R.id.MarioCharListView);
        final ListView lvMarioBike = (ListView) findViewById(R.id.MarioBikeListView);
        final ListView lvMarioKart = (ListView) findViewById(R.id.MarioKartListView);
        btnMarioChar.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                setContentView(R.layout.mariochar);
            }
        });
        btnMarioKart.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                setContentView(R.layout.mariokart);
            }
        });
        btnMarioBike.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                setContentView(R.layout.mariobike);
            }
        });
    }
    
}

XML's

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
<ListView android:id="@+id/MarioCharListView" android:layout_width="fill_parent" android:layout_height="wrap_content" android:entries="@array/mariocharlist"></ListView>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content">
<ListView android:id="@+id/MarioKartListView" android:layout_width="fill_parent" android:layout_height="wrap_content" android:entries="@array/mariokartlist"></ListView>
</LinearLayout>