Games : Skyrim crashes after attempting to launch?

Does anyone know how I can repair this issue (it has been going on for at least a year or so now, and I have not been able to play it on my main rig because of this)? When I try to play Skyrim it crashes after I hit play in the launcher (it waits a while loading, and the crashes and sometimes I need to restart my computer). I have already tried removing the Skyrim Prefs file, and then having Steam repair it but it still is not working.