I use TightVNC. Works perfectly for me. I can see everything that's shown on my tv - and just as it is shown on my tv. It doesn't use much memory either.
Does this mean that it updates your Viewer PC quickly enough that the video screen gives a smooth image?
I have used both VNC and TightVNC and find that the speed at which they update the Viewer PC is quite slow and unwatchable, but still usable for administration purposes. This is over a 100 Mbps wired network connection.
No, I got the same "1fps-feeling" when playing videos over vnc :-\ But for administrating purposes it works great.