I actually have two questions, but I'm thinking one answers the other.

The network consists of a Windows 2003 server and several windows xp
professional workstations. The windows 2003 server has been dcpromo'd
to a PDC...

On the XP workstation- if the user logs into the domain they can not
edit things like devices in device manager because that user does not
have administrative rights. When logged in to (this computer) instead
of domain, the user can access things like device manager. I'm assuming
that this is because when logged into (this computer) the local
permissions are being used instead of domain/2003 server perm's. How
can I make a user log into the domain and have admin rights to their own
computer at the same time? Is this like a non-privileged user for a
reason? As in, should I only log on locally when needing to perform
admin tasks and login to the domain the rest of the time. Does that
make the computer more secure or something to that degree?

Secondly, if I share a printer on my XP professional workstation (while
logged in locally), other XP professional workstations in the domain can
not access the share, or even browse for available shares without a
username/password box popping up ...do not have a valid user
account/password. If I login to the domain, then the XP workstation is
able to be browsed via My Network places and shares are able to be
viewed, etc.

To tie it all together: How can I have a user login to the domain, have
full admin rights of their own computer, and offer a printer to be
shared to other users in the domain?

Hope that made sense.