You may get this error during MOSS or WSS installation on 64-bit Windows Server:
Setup is unable to proceed due to the following error(s):
Internet Information Services is running in 32-bit emulation mode.
Correct the issue(s) listed above and re-run setup.
To fix the problem disable 32-bit support in the default application pool settings.
From IIS Manager -> Application Pools -> Set Application Pool Defaults, set the "Enable 32-Bit Applications" to False.
Or run this from your Intepub/AdminScripts folder
cscript adsutil.vbs set w3svc/AppPools/Enable32bitAppOnWin64 1