If you don't want an entry to active the next time you boot or login you can either disable or delete it. To disable an entry uncheck it. Autoruns will store the startup information in a backup location so that it can reactivate the entry when you recheck it. For items stored in startup folders Autoruns creates a subfolder named Autorunsdisabled. If there are disabled items in these folders when you logon Explorer will create a window to the folder on the desktop (but not execute the images within it).
You should delete items that you do not wish to ever execute. Do so by choosing Delete in the Entry menu.