Class Instantiation when to use/or not

[C# Programming]

Hi all,

I've been trying to become more familiar with classes and instantiating them and the different times one would need to do so. I came across the following tutorial (http://www.csharp-station.com/Tutorials/Lesson05.aspx[^ (http://www.csharp-station.com/Tutorials/Lesson05.aspx)]
and it has the code below. Albeit, this code doesn't do anything useful, but again, just raises a question. The question I have is what would drive instantiating the class versus declaring getChoice() as static? As I'm a ME, please use plain english. http://www.barakasoft.com/script/Forums/Images/smiley_biggrin.gif using System;

class Address
{
public string name;
public string address;
}

class MethodParams
{
public static void Main()
{
string myChoice;

MethodParams mp = new MethodParams();

do {
// show menu and get input from user
myChoice = mp.getChoice();

// Make a decision based on the user's choice
mp.makeDecision(myChoice);

// Pause to allow the user to see the results
Console.Write("press Enter key to continue...");
Console.ReadLine();
Console.WriteLine();
} while (myChoice != "Q" && myChoice != "q"); // Keep going until the user wants to quit
}

// show menu and get user's choice
string getChoice()
{
string myChoice;

// Print A Menu
Console.WriteLine("My Address Book\n");

Console.WriteLine("A - Add New Address");
Console.WriteLine("D - Delete Address");
Console.WriteLine("M - Modify Address");
Console.WriteLine("V - View Addresses");
Console.WriteLine("Q - Quit\n");

Console.WriteLine("Choice (A,D,M,V,or Q): ");

// Retrieve the user's choice
myChoice = Console.ReadLine();

return myChoice;
}

// make decision
void makeDecision(string myChoice)
{
Address addr = new Address();

switch(myChoice)
{
case "A":
case "a":
addr.name = "Joe";
addr.address = "C# Station";
this.addAddress(ref addr);
break;
case "D":
case "d":
addr.name = "Robert";
this.deleteAddress(addr.name);
break;
case "M":
case "m":
addr.name = "Matt";
this.modifyAddress(out addr);
Console.WriteLine("Name is now {0}.", addr.name);
break;
case "V":
case "v":
this.viewAddresses("Cheryl", "Joe", "Matt", "Robert");
break;
case "Q":
case "q":
Console.WriteLine("Bye.");
break;
default:
Console.WriteLine("{0} is not a valid choice", myChoice);
break;
}
}

// insert an address
void addAddress(ref Address addr)
{
Console.WriteLine("Name: {0}, Address: {1} added.", addr.name, addr.address);
}

// remove an address
void deleteAddress(string name)
{
Console.WriteLine("You wish to delete {0}'s address.", name);
}

// change an address
void modifyAddress(out Address addr)
{
//Console.WriteLine("Name: {0}.", addr.name); // causes error!
addr = new Address();
addr.name = "Joe";
addr.address = "C# Station";
}

// show addresses
void viewAddresses(params string[] names)
{
foreach (string name in names)
{
Console.WriteLine("Name: {0}", name);
}
}
}