optimal settings for ingame counter-strike 1.6 vary from person to person,though certainly there are few things to remember that is logical.
first of all counter strike is a fps based game with little or no graphics.so better go with 800*600 resolution than 1024*768game is viewed closer with little bigger objects.
using noforce command is another trick where you are forcing few in-game settings by default.see here for noforce
disable mouse pointer precision from your pccontrol panel mouse settings.
disable all options from mouse in-game except raw input and mouse look
disable translucent from in-game
type in console cl_dynamiccrosshair 0 to disable crosshair size fluctuation when firing.
disable unneccessary graphics option from your gfx(if you have) like vsync,tripple buferring,threaded optimization.
also type in console gl_vsync 0to disable vsync
server rates is the rate of response(packets) the server is able to sent you.client is the rate of acknowledge of recieved packets from server and sending forth. its not 100% synchronized.