If you don't pay games (or music), you may as well leave it as it is.
If you go to Start > Run, and type
you will get all sorts of information about your version of DirectX. In particular, the last line on the first page lists your version of DirectX, which I suspect is DirectX 7. To my knowledge, there never was a DirectX 4.07, although there are several components of DirectX with that version number, and it may well appear in the bottom left corner of the first page referred to above.