How to disable Windows Defender

On your own head be it, Open w/defender then goto TOOLS - OPTIONS & uncheck all the boxes.
Then goto w/Firewall and ensure defender is not in use there. By disabling defender you are also interfearing with microsoft updates for other programes other than just defender. Remember vista is still a baby and is constantly being updated,new service packs are being created day by day to improve the "ultimate operating system" lol yeah right. I disabled mine last year and had nothing but trouble.firewall wouldnt let things in/out ,internet kept crashing.I eventually had to uninstall the nightmare that is NORTON anti virus. and find a program that would work well along side defender and the one i recomend is AVG. its free,easy and defender loves it.Defender is a major part to the whole windows operating system.I dont think you can fully disable it as you will find out eventually.