To answer part of my own question:
There are several ways in which you can accomplish dynamic DNS updates from a linux box to a Win2K DNS Server. The Win2K DNS Server is in fact RFC 2136 compliant, and uses TSIG keys for secure updates. TSIG keys require a "shared secret" to be known by both computers in order to generate and decode they keys. Windows uses Kerberos to distribute these secrets, and in what way im not quite sure yet (more to come on that later).
I did sucessfully get an A Host record inserted into an Active Directory Integrated Zone on a Win2K Adv. Server. Here are the steps I followed.
1.) On the properties of the Forward Lookup Zone that you want to update, goto Properties->General and make sure "Allow Dynamic Updates" is set to YES. This is a slight security hazard, considering a hacker could spoof an IP address and then register/modify/delete entries in this Zone.
2.) From your linux machine, draw a Dynamic IP address and make sure the DNS Server it got is the one you want to update to, then run the nsupdate command in the console.
>update add <your hostname>.yourdomain.com A <your IP address>
*note: you need to have that blank line in there before you quit, its what sends the command to the DNS server.
Now check your DNS server...there should be an A record in the Forward Lookup Zone of your domain.
This way of course is not acceptable since you dont want to have to run this command every time your draw an IP. You can also edit your dhclient.conf file and have the DHCP server authenticate for you. For more on that config, see this page.
Another Reference I found usefull.
If I figure out the Kerberos thing...I'll post more