A current Windows installation should have all the files necessary for running games that rely on DX9, 10, and 11 without you needing to do anything other than the minor updates that get packaged with the games themselves, or via Windows Update.
Crysis 2 runs in DX11 mode on compatible systems anyway. You can try to install the DirectX packages, but chances are they will run and finish without really doing anything. I think your problem is something else.