I have rolled MOM out to many Windows 2000 servers and there are a number of things to look out for when planning to deploy.

WMI Providers for AD management

There are a couple of WMI providers that have to be installed for the effective management of a Windows 2000 AD with MOM, it is good practice I have found to install these before you deploy both the AD and DNS management packs.

DNS - The DNS WMI  provider (dnsprov.dll) is available with the MOM 2000 resource kit, alternatively you can download this provider at the following location ftp://ftp.microsoft.com/reskit/win2000/dnsprov.zip

There is also a hotfix available for this that fixes a memory leak issue, which I also always install, details of which can be found here: http://support.microsoft.com/default.aspx?scid=kb;en-us;822849

AD - The AD Replication provider (replprov.dll) is available with the MOM 2000 resource kit also, again this has a potential WMI issue, so I always download the patched version, details of which can be found here: http://support.microsoft.com/default.aspx?scid=kb;en-us;889054