NT server in 2000 domain problems

[Chem]

I have a problem with an NT server in a 2000 domain where I work. Like some sort of fool I offered to set up new servers (no IT department) and they came with Windows 2003 preinstalled. Fine, I thought. Wanted to have a look at it anyway. So I read a bit and it became apparent that there were going to be some issues.

I joined the server to the domain fine, then wanted to set it up as a backup domain controller (our PDC is a Win2k machine). I started to run the adprep utility, and got so far before it stopped with an error regarding an FSMO Role not being configured. Okay, I thought, this is a little harder than I expected. Please bear in mind I'm no network manager, just thought I could help out as I know a bit.

There was an immediate problem when anyone tried to log on: it returned an error saying "There are currently no logon servers available to service the logon request". Resetting the DC cleared this up.

I left it a while to do some more reading up on the topic, only to field several calls moments later from the finance department saying they had no access to one of their network shares. Each person in that dept. has their own M drive which is on our crappy NT server.

I reset the server, and they could each access their M drives. For a while. Then the calls started again. I checked the properties of the share, and it recognized the names from Active Directory just fine initially, but I checked again when I took the calls I checked again, only to see Account Unknown in the share properties.

I can ping machines in the domain from the NT server, but I can't browse the domain, and can't ping the domain controller. I cannot access User Manager in the Administrative Tools.

The Domain Controller can ping everything, including the NT server except when I just use the server name.

The client machines (Win XP) can ping both the DC and the NT server.

What I've tried:

creating the Lmhosts file on both the DC and the NT server. This did nothing.

Changing group policy to allow anonymous SID translation. Bit of a security risk, but I was kind of desperate.

Can anyone offer anything? I don't think I'm missing anything out, but question away. I'm no longer at work, but hopefully I'll be able to remember stuff.