I moved this to SecurityCenter 9 - 2009 which I am assuming you still have.
Double-clock the taskbar icon to open SecurityCenter
Click Advanced Menu (bottom)
Click Configure (left)
Click Computer & Files (top left)
In the right-hand space you can disable VirusScan and tell it for how long.
That normally is all you need if this is to install something that asks you to disable protection. However if you also need to disable the firewall
in step 4 above click Internet & Network (top left)
If by any chance you already have the 2010 version then do the following:
Double-click the taskbar icon to open SecurityCenter
Click Real Time Scanning (top)
Click Real Time Scanning Settings (right)
You can disable Antivirus there and tell it for how long
If you need to disable the firewall then click Firewall then Settings.
There is no need to disable anything else and in fact you can't without causing major issues.