Install them and give it a try, both are free and not a big deal to set up.
My Take.
I use RDT between spots that I need to Connect to Repetitively for long periods of time, and on the other side there is someone who understands how it works. I would set it up, and insist that No one would touch the settings.
RDT is very good to keep a Remote system with a server (like Windows2003) with system that consists on Domain etc. RDT is more like an OS thing, VNC just an application.
When casual remote is needed between two computers or to interact with individual computers that are part of e regular peer to peer Network, I use Ultr@VNC. It provides:
Remote Control, File Transfer, and Chat between LAN computers or over the Internet. It takes only few minutes to set.
For security purpose, and System's load reduction I want the remote out of the picture once the session is terminated. Ultra@VNC and few other VNC variants provide this capacity.
In most cases, even if some one "played" with the system I still will be able to connect with VNC.
Once you close VNC it has no further impact on the system.
Link to:
Ultr@VNC - Installation, and Settings.
Link to:
How to use remote Desktop Access in Windows XP
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