Yes but two points. Many freeware planes use one of the default panels or sounds useing the 'alias' comand to them directly. Remove the defaults and they now won't work. Second, if you every fly online, you NEED the default jets otherwise evryone apears as a Cessna!

Why not just use the simple PAI uninstaler that you already have?

BTW, if you need some help, send me a PM and i'll talk you through it.