Terminal can be found in your Applications>Utilities folder. It's a command line interface to Mac OS X. The instructions provided by disguise are just a way to find and move a file from your Library folder. You won't hurt anything by trying out what is suggested.
Did you try posting on the MS Office forum? Any joy there?
I just tried the commands that disguise posted - too many arguements with the
cd ~/Library/Saved Application State/com.microsoft.Word.savedState
Maybe he/she will post again.
I did find the directory that he/she has suggested moving:
It's in your User>Library folder (to access your user Library, go to Finder and hold down the option key while clicking on the Go menu). Maybe he/she just means that you should move that folder to the Desktop (with Word closed) and then reopen Word and see if you've the same problem. If so, then you could always just put it back. No need to go through Terminal, it seems.
The "too many arguments" error message refers to the fact that the "Saved Application State" folder has blank spaces embedded within it. The C-shell parses the "cd" command and finds too many arguments. This is my fault for not making this clear. Sorry.
In general, what I was recommending you to do was to move the file "windows.plist" in the folder
~/Library/Saved Application State/com.microsoft.Word.savedState
Now I need to clarify that ~ (tilde) gets translated by C-shell to the users home directory - for example
~/Library gets translated to /Users/Kigali/Library
(For more information - you should read up on the C-shell)
To remedy the situation - you can follow Clinton's lead and use "Finder" to perform the same function
that I originally prescribed. Hope this helps