The DLL-file you have a problem with belongs to QuickTime which is needed for iTunes to run properly. You should try to reinstall QuickTime to see if it helps. A quick not though, after you've uninstalled QuickTime from your computer, go to C:\Windows and do a search for qtcf.dll, delete any qtcf.dll-files you find.
If the problem is with the file itself, it is best to remove it from Windows system folders so that when you reinstall it you get the correct version.