You could go to Add remove programs and remove it from there if it is on it.
But if you have windows messenger it will remove that as well.
If it is just the update you want to stop run windows update manually and when it shows click on security essential and a box will open underneat.Tick the little square saying don't show update again.That should do it.
But I would check Add remove to see if you have it on there.
You remove that and you will probably remove a few more programs with it.