If the laptop is old and slow, just use the xcal for data logging, that way the refresh rate is good.
If you go to SCT's web site they have directions. It is too complex for me to explain, I know it wouldn't come out right anyway. The best way is to just get out and do some hands on to understand how to do it.
Your going to need a USB cable to hook up the xcal to the computer to load the configuration file to the xcal and to get data from the xcal to the computer. Then you can pick the PID's you want to log, save them in a configuration file, then upload it to the xcal. Then hit the street, log away, come back and upload to the computer and review.