You need to be more specific about what you wish to accomplish and from
where.
Remote Desktop from outside your network can be accomplished by (one way)
changing the listening port for remote desktop on most of your internal
machines (all except one) and forwardig those ports appropriately on your
router to each specified computer. Then you remote to the external IP
(dyndns name) and add "ort#" to the end - so it knows where to go.
If you mean internally - just configure the internal firewalls to allow File
and Printer sharing on the local network.
Without more specifics on your setup and what you are trying to do - there
is some general ideas.