Windows Backup plan advice for multiple sites

Are you just backing up file servers? I have 12 remote sites. Each site has a single read only domain controller that is also a file and print server. All files are accessed through a unified DFS namespace. I replicate all files between the main site and the appropriate branch(es) using DFS. The advantage is that if the branch server is to go down, I can use DFS namespace to redirect users to another copy of their files over the WAN. Once their server is repaired, we wait until everything has replicated back and then repoint them back to the local server using DFS namespace.

I enable a shadow copy schedule on the fileservers, but they don't otherwise have any local backups. All backups are done against the centralized copy of the files. All replication is done over a 1.5 mbit T1. Some branches have up to 200 GB of files that are replicated. DFS replication only replicates changes bytes in files and is very WAN friendly. I limit the amount of bandwidth it can use during the day.

You could replicate everything to the site you are at and then 1 other site in case you lost your site.

Two domain controllers at each of your sites seems like major overkill (unless you have very large sites). As I said, I have just single servers supporting the remote offices. I would make sure that your servers support full remote out of band management and virtual media management such as HP iLO or Dell DRAC Enterprise. That way, you can see what is on the screen, go into the BIOS, power cycle the servers, etc. Without trying to talk someone through it over the phone.  

Hi, i really appreicate your suggestion and explanation.
This is my first live setup of AD, and although i've done the exams and have a test domain set up etc, i dont have live experience and this is one area where i need to get advice on the best way to backup/restore the servers.
It will just be Windows 2008 servers that i'm backing up, each site will have approx 80 users and computers.
Its not going to happen until next year, so i will have a good read up on DFS and set it up on my Test domain to get up to speed with it.
If one of your RODC's blows up, do the clients autmatically go over the WAN to get authenticated by a different DC? Do you use Windows Backup and IFM to repair your RODC or do you use Backupexec or just reinstall from scratch?
Sorry for the extra questions, thanks for your help,
Rick

Many thanks for your time and help with this, Its much appreciated and your solution will also save me some money which will push the project through quicker. Cheers, Rick