Hi Arakai,
Not sure what you mean.
If you want to get rid of the security shield icon from the taskbar Notification Area, then step 7 in this tutorial will show you how to.
Security Center Alert Warning Notification
If you want to get rid of the security shield icon from all the icons like the shortcut arrow, then this is not possible that I know of. It is there to let you know that the item it is on will require administrator approval first (UAC).
Hope this helps,
Shawn