Your culture name: en-US (IE -> Tools -> Internet Options -> Languages)
Your date format: 2/5/2012 7:27:07 PM

en-US date format: 2/5/2012 7:27:07 PM
en-GB date format: 05/02/2012 19:27:07
ISO date format: 2012-02-05T19:27:07

using System.Globalization;

DateTime d = DateTime.Now;

CultureInfo YourCulture = CultureInfo.CurrentCulture;
YourCultureName.Text = YourCulture.Name;
YourDateFormat.Text = d.ToString(YourCulture);

CultureInfo EnUsCulture = CultureInfo.CreateSpecificCulture("en-US");
EnUsDateFormat.Text = d.ToString(EnUsCulture);

CultureInfo EnGbCulture = CultureInfo.CreateSpecificCulture("en-GB");
EnGbDateFormat.Text = d.ToString(EnGbCulture);

IsoDateFormat.Text = d.ToString("s");