I have 6 GPOs that install software, and 1 other GPO which just sets the "wait for network at logon" setting (with user settings disabled). My test client happily boots up quickly after all the software GPOs have been applied.
However, I created a new GPO (computer settings disabled), and just redirected "My Documents" (which is empty at the moment) to a dfs share on my server. Now, when I reboot, the computer hangs at "Applying computer settings" (which is strange considering the computer settings in the new GPO are disabled). I've deleted this GPO, and recreated it and the effect is the same.