Help: Connecting MAC's to Windows Network.

Hello all, my first post here. I’m looking for a little help, in fact any and as much input would be truly appreciated. I’m currently working on a campus in a Win. 2003 network. I’m looking to add a MAC lab into the mix and I’m really trying to get the jist of the whole cross-platform networking, between MAC’s/PC’s. I do understand that you do have the ability to authenticate through AD on the MAC, via Open Directory Access. Now, my question is, do I need an XServer to do this? Or can I simply run OD on a standalone MAC? It’d be best to have it run somehow on a windows platform. With that said, it leads me to the actual workstations. I need to know the best way to lock down the individual workstations. What is the best way, OD Workgroup Manager? Ideally I’d like it to replicate the Group Policies set on AD. I’m going to be imaging these so locking them down and standardizing the desktops is essentially my goal. Again I appreciate any and all help! Thanks.