That way is as good as any I think really. I suppose you don't really need the call the String.Format() in this example as you are only displaying the one thing on it's own with no formatting. You could just simply do this:
That is equivalent to your line of code. Obviously though, if you want to include any formatting, or include the DateTime as part of a sentence for example, String.Format() is a good way to go . You can put the string in a label, a normal text box etc.