in reply to ms-word document comparision

Here you go:

First open the link to the ActiveState documentation. Look up Win32::OLE and check out the example.
Next open word and hit F11. This opens the VBA window. Hit 'F2' or 'View->Object Browser'. Type in "compare" and read the info on how to call the compare method. Hint the example does exacly what you want to do, saveing to a new file.

Now write a script in Perl that creates a OLE connection, issues the compare method, and closes.

If you do not have word installed, then you are going to have to export the data out of word with another application.