First, to know which service pack you have, you can right click my computer icon and get the information there.
Alternatively you can run --> dxdiag and get all information here as well.
To configure soundmax speakers to give the 5.1 config, you will have to install soundmax sound manager (comes with the cd, i Guess) The icon will appear in the taskbar once installed. Install sound driver properly and reboot when prompted (multiple times if required).
Once you open the sound manager, you will be able to change setup from 2 speaker to 5.1.