Whilst installing SQL Server 2005 for our customer, it got stucked in when the installer is in the Setting File Security of the Configure Database Service step of the installation. Tried checking through the event logs but no errors were recorded.
I opened the installation log file and looks like the installation got stucked in the Write_sqlFileSDDL action.
A quick search over the internet eventually lead me to http://support.microsoft.com/kb/910070
CAUSE: If the Domain has alot of external trusts with other domains the time required to lookup through the domain group names increased significantly. Therefore installation time will increase as well.
RESOLUTION: Though you can request for the download of the hotfix, I took the workaround METHOD by disabling the network and kickstart the installation. Worked well without any problems.