Method 1

1. use MHTML-Converter, this strips out all the files and dumps them in to a folder. the html it creates is shit.
2. open the htm file in a web browser, i used internet explorer. select all, not the source, and then paste in to the design page of a fresh html file in adobe Dreamweaver CS3.
3. All the pictures might need to be re referenced, but should be easy enough.
4. If using for joomla dont forget you don not need all the header info or body tags etc..

 Nb if you have the word version save as web filtered html

Method 2

You can change the file extension on the file from ".mht" to read ".uue".
You can then open the ".uue" file up in a zip program such as WinZip.

You can then extract one or all the files contained in the renamed .mht file
using the WinZip program interface.

Of course, you will have to change the file extensions on the extracted
files because the extracted .html file will have a .txt file extension when
extracted. For instance, when you are viewing the .uue file in WinZip the
.html file will have the name 0001.txt and will also have that name and
extension when it's extracted. So once it's extracted just change the name
of the file from 0001.txt to myfile.html for example. Likewise, image
files contained in the .uue file will contain extensions such as .001, 002,
etc... and will have to be renamed with thier proper extension once they've
been extracted.