We just recently started having an issue with remote desktop we can logon as local admin, but not domain admin the screen hangs and never logs in

Does the error say something like, "A policy does not allow you to logon interactively to this site?"

This means a group policy for logon interactively/logon locally may have been created that prevents you from logging on.

No error message pops up it just never connects so we have to terminate our attempt to connect.  We can go into Computer Management and connect to look at Event Viewer but haven't seen anything that relates to the issue.  We've been having this issue will several of our servers.

What service pack are you running on the server?

Are you running any 3rd party sw for security?

I will have to check on the service packs, but our third party software is Sophos

Could be a profile problem.
Try to create a new domain admin user without set a roaming profile.
Then try to logon to one of your terminal servers with that account.

If it is ok try to (ATTENTION: POTENTIALLY LOST OF DATA) delete the profile (roaming and locally on the terminal server) of one of those domain admins that have logon problem and try to logon on that server with that domain admin.

I checked on the  Service Packs and this server has SP2 for 2003 Server.  Over the weekend I re-booted the server and RPD seems to be working fine, but still not certain is at the core.  If I was present at the remote site (six hours away) I would create the new domain admin and remove the other that may have to be on a trip some time down the road.