The programs in the menu all go to the same executable program, theoretically they could start you at a specific skin of the interface but they don't.
So I can think of no reason to keep them all, since you can skip to different skins from within the "Advanced settings" tab, but I would do it as a stepped process.
Make sure the recycle bins not in automatic empty mode, then delete the ones you don't want, use it for a while before emptying the recycle bin.