I have had problems with the lag issue with vnc. The best optimizations for tightvnc 2.6 I have tested can be set up in this manner.
1. When you log on to the javaviewer click on the set options button (the farthest button to the left on the javaviewer top control bar.)
2.Make sure the settings are as follows
a.)Preferred encoding is set to tight.
b.)Color format is set to servers default
c.)Turn on custom compression level and set it to "Best"
d.)Turn down jpeg quality the lower. the quality the faster the refresh
e.)Make sure that copyrect encoding is checked
3.Make sure your server (control is located server side in taskbar) has the following settings
a.)screen polling cycle is set to 30ms (you cannot set this lower your network may not be designed to transmit and recieve encoded material that fast.)
b.)download spy++ to get individual window class names for any fullscreen video windows you may use and enter it in the video tab. Please note that some video classes (such as vlc player) do not stay the same after each use. :-( sorry i don't know how to get around that. However flash media player is the same all the way around.
Thats it. I believe this is the best video performance this program allows for machines that have mismatched resolutions. Your optimum performance with come with machines that have matched video resolutions.
I know that my network can handle better polling however unless there is a hack out there that releases the 30ms polling rule or another vnc server (any suggestions?) that will allow me to get better polling then I don't know how to optimize video performance any further than this.