PDC rebuild - should I restore or dcpromo?

Hi experts,

I have a problem and I'm not sure which way to resolve it. My organisation has 2 domain controllers (DC1 & DC2) in a Windows 2003 Active Directory environment which has a trust with an old NT4 domain set up and Exchange 2003, SQL servers etc etc all in the AD domain.

Due to a problem with the RAID array on DC1 (the PDC), I need to rebuild the server. I have DNS running on both DCs and both are global catalog servers (DC2 did not used to be, but I enabled it when DC1 was offline due to hardware problems).

As I see it, I have two choices:

1. Switch off DC1, rebuild the array and install Server 2003 then restore the most recent backup (entire C drive and system state)
2. Dcpromo DC1 so as to bring it off AD, rebuild, reinstall and dcpromo it back again

If I go to option 1, will I get away with fooling DC2 into thinking that DC1 was simply offline for a couple of hours? Also, can I just do a normal restore, or do I need to go into Directory Services restore mode?

If I go for option 2, what do I need to do to ensure all FSMO roles are moved to DC2 and there are no orphan roles or any other gotcha's lurking around to get me?

Please advise - I do have quite a bit of experience of AD, but I'm still nervous about breaking it as so much of the organisation is integrated with it now.

Thanks