This is done using the cloning tools available from the Win2K Server Resouce Kit. There will be a couple of bumps along the way
I suspect that at present you essentially have 2 separate AD forests/domains: burlea.local on your original DC, and burlea.org on your second DC.
The problem you will have (if you accepted the default NetBIOS domain names) is that you have two domains with the same NetBIOS name (BURLEA). This will probably prevent you from creating a trust relationship (you can try, but I'm pretty sure it won't work). You must be able to create trust relationships to perform a migration.
Assuming the above won't work, your options come down to the following:
1. Recreating all your User and Group accounts, and joining all computers to the new domain.
2. You cannot change the domain name (either AD or NetBIOS) without running dcpromo. So demote the DC, and recreate your domain as burlea.local, but using a different NetBIOS domain name.
You have a bit of reading to do. While the procedure is fairly straight-forward, the steps to follow contain far more information than will easily fit in this forum. Chapter 10 of the Win2K Server Resource Kit - Windows 2000 Server Deployment Planning Guide (available either in print or online at Microsoft TechNet) has most of the info you will need. (The tools you will need are included with the printed version and aren't available online).
Depending on the number of users and groups you already have created, you may find it faster (and less expensive) (Win2K Server ResKit goes for about $250, depending on where you get it).
The downside to option 2 is the the NetBIOS domain name is what users see in the domain window of the log-on screen. You willneed to forewarn users to expect something different than what they are used to seeing.
Good luck.
