Dreamweaver CS4 Clear the "Open a Recent Item" window
***** But you must be in the user profile that you created the website with or you will not see the Recent list folder in the registry !!!!!
***** you will have registry rights to Delete files that user created.
**** If you do not have authority, you must find the user profile as an Administrator.
type REGEDIT in the run box
then in the registry got to,
There will be a "Recent File List" you can delete all the files inside of it.