XP Style Controls in Windows 2000

We are building an ASP.NET based application using web forms in Visual Studio .NET. We'd like to make sure that our form controls such as dropdowns, calendars, listboxes, etc. have XP Style when the user runs them in the Internet Explorer under operating system WIN2000 or XP. I know this can be done as I have seen some applications working this way. Any suggestions how I can do the same? Your help is much appreciated. Thanks, Saeed