>Something like this would work (you'll obviously want to verify the image types, add some error/exception handling). I'm also assuming you're using the FileUpload control. This code could go in the Click event of your "Upload" button.
>
>

>System.Drawing.Image img = System.Drawing.Image.FromStream(this.FileUpload1.PostedFile.InputStream);
>System.Drawing.Image thumb = img.GetThumbnailImage(100, 100, null, IntPtr.Zero);
>thumb.Save(@"C:\Sample.jpg");
>

Thanks