you can paste all that stuff into a file called config.cfg which you can find in the data folder.
You could also just open the console and type exec n_low.cfg, enter and type vid_restart and enter.
But I rather think you've got some bad drivers. For Nexuiz you need a proper openGL support. There was another guy posting about heavy lags with an X1300@Vista in the support thread. He updated his drivers and his performance problems were solved.