With Windows 7, as well as giving the operating system a new look and the ability to personalise the interface to suit you, Microsoft also implemented a number of features designed to making computing easier. Among these was the ability for Windows to remember which files, folder, websites and applications you have recently used, and then display them in the Start Menu offering you quick and easy access to them. However, you may want to clear these lists and start again. Here’s how to remove recently opened programs from the Start menu.
From the Start menu, select Control Panel.
Select Appearance and Personalization and then choose Taskbar and Start Menu.
From the Windows that appears, select the Start Menu tab.
To clear recently opened programs uncheck the box next to Prevent recently opened programs from appearing in the Start menu, clear the Store and display recently opened programs in the Start menu check box. You can also uncheck the box next to Store and display recently opened items in the Start menu to remove recently opened Jump lists.
Press Apply and then ok. Next time you press the Start menu, there will be no recently opened programs listed (unless they have been pinned to the start menu)
If you want recently opened programs or items to be displayed again, simply return to the Start Menu section in the control panel and check the boxes under the Start Menu tab in the window that appears. Then press Apply and OK to close the window.