This really depends on the OS involved. You said for Mac at the end of your message so I'll stick to there.
On the Mac, erasing the previously opened/viewed items in the menu list is pretty easy for all OSX apps as you've got the "Clear Menu" option at the bottom of each and every File menu for "Open Recent." Click that and the menu clears and is deleted (empty trash thereafter as well which does some basic cleanup, although these are system files). Bookmarks on the Mac are a different animal and you'd have to had manually created a bookmark to have one there. But assuming you have (I suggest you don't for porn DVD's) then go into Window/Bookmarks and you'll see the ability to edit bookmarks you've made, including deleting them.
Now the HISTORY of all DVD's you ever watched are stored outside the application menu's. I'm assuming you are running Leopard but I think Panther kept the files in the same area. In Leopard, your DVD viewing history is stored in User Name>Library>Application Support>DVD Player>Settings. If you go into there (visible via Finder) and delete all files present EXCEPT "Global Settings.enc", you'll no longer get the prompt of "would you like to continue watching this previously viewed DVD blah blah blah" prompt. Your history is wiped. Make sure to empty trash when done as well. Note that you'll whack your bookmarks also in doing this so I only recommend wiping it if you are sharing that laptop.
This obviously assumes you are using a shared Mac. If you are the Admin account on the Mac, you don't really need to worry about this too much.
Edited by - lubenluv on 12/19/2009 10:02:42 AM
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