This is HOW to question

Hi every one
I need some info
it is actually two questions:
First:
Every time I make changes or test or addition to a page it create a copy in DB so if I need to go back and fix the problem I create ( and I do it some times) I can get back to version before and restore data and configuration to original state, now here is my question, some of the pages have bunch of copies is there any way to remove some and live some ?
I know it probably can be removed for DB manually but I was hopping there is another way.
Second
I am working on a design and I have a situation where I need to be able to have a menu list to be shown only on several pages IE like an product page would have a list of pages with different products, but this is menu should be only for specific pages and not shown on the rest of the site..
I hope I am clear with the explanation..

Any suggestion?