Bringing up the DC

on my network i have 2 win2k DC. DC1 & DC2. DC1 is acting main DC which has all the five roles ( GC, DNS, RID,PDC, INfrastructure master) DC2 is just a backup DC not having any domain Specific roles. now my DC1 has crashed we are using DC2. clients login using WIN2k PRo & Win 95 & Win98 . we are not able to do any changes on Domain. since the DC1 has crashed now how do i bring back my main DC (i.e DC1). none of the roles have been transfered to DC2. DC1 is formatted now. please give step-by-step guidlines on bringing up the DC1 succesfully.

2) After bringing up the DC1 will the AD Data get replicated from the backup DC2