Logon locally rights doesnt sound right to me for web access on domain contorllers. If this is true then IIS web access will be denied for all users on domain controllers by default, which I don't believe is the default.
Correct me if I'm wrong.........
This is another reason why you shouldn't install IIS on a domain controller, as the IIS anonymous user account is typically added by default. Here's a screencap of my DC that has IIS on it (hardened with IISLockdown/URLScan):

As you can see, there's an "IUSR_blah" account under logon on locally, and that is automatically created by default. This is another reason why FTP under IIS while on a DC doesn't work be default, because the users need logon locally rights in order to access the box. It would *seem* like logon from a network permissions would be enough, but they aren't.