Load Runner 9.5 - Analysis

does anyone know if i need to monitor other system components in my load test , do i add them from windows resources - i fail to read its analysis report ( Max and Min and their Scale thing i dont get it )?
Or i have to have site scope , if i do , which sould i install, HP or HP with LR???
all i need to monitor is CPU usage and Memory
and in the User guide there is nothing about site scope installlation ?

Seems like in each component there is a riddle to solve=)
Thanks
Marlin