Remove task killer. Killing tasks actually decreases battery life. This has been discussed many times before and you will see several discussions regarding this thread. Basically uninstall ATK and ignore running apps.
Android is designed to keep running services that are required to be running due to interconnected dependencies.
Why you don't need a task killer
Advanced Task Killer
read the links, and you will see your explanations. Just to cut the entire story short, don't bother with task killers, they reduce battery life and reduce performance.