Program.cs

using System;
using System.Globalization;
using System.Threading;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            var culture = (CultureInfo)CultureInfo.CurrentCulture.Clone();
            culture.DateTimeFormat.ShortDatePattern = "01/01/2000";
            Thread.CurrentThread.CurrentCulture = culture;

            Console.WriteLine(DateTime.Today);
        }
    }
}