We had an array lose 3 drives on an IIS6 server. We now have the drives runing...for now. What's the best path to restoring the server to functionality. We have a backup of system state and the interpub directory.
When you say "We now have the drive runing...for now.", you make me think that you haven't resolved your issue with the hardware. You really ought to do that before investing a lot of time in rebuilding the box.
If Windows is totally gone, and all you have is the \inetpub directory and the System State you might, potentially, be missing application software that kept files outside those areas. Keep that in mind.
In general, though, you should be able to reinstall Windows with the same computer name, partitioning scheme, and name of the \Windows folder, restore the System State backup, and put back the \Inetpub folder.
If the box was a member of a domain you may have to disjoin and rejoin the domain after restoring the System State backup (depending on how old it was).
If the box was a Domain Controller things become a bit more difficult.