For individual items that display in the start menu that you do not wish to show - right click then click remove from list, it should not display again.
For:- if you do not want flesh installs to show in menu'( have not use them yet )
On the Start button, bottom left, right click and select properties,
Click on the start menu tab -> click on Customize Start Menu .
Uncheck highlight newly installed programs (between Games and Music) then click OK then Apply then OK
For recently used items/ programs not to show (they can show from other sessions even if not used in this one) :-Click on start button right click and select properties .Click on the start menu tab -> in privacy uncheck items list you do not wish to be shown.
I hope this helps