> If I use HTTrack to save website, say yahoo.com, to
> a local machine, can I use this local machine as a
> http server and access the saved yahoo.com offline
> pages through URL?
A mirror is a collection of files (open the index.html)
or use the url equivalent 
<file:///C:/Users/Bill/zHTTrack/index.html>
in the browser.

A mirror is NOT a copy. There is no server. Forms will not work.