I managed to find out how to do this on the Website:
http://www.mvps.org/accessPete
>Hello,
>
>I would like to laod up the Windows default application (if set) for a file that the user selects in an Access grid. For example, the grid may show a .doc file and I would like to load Word (or whatever the user has set for documents) to view this.
>
>I am currently using the Shell function, but need to specify WinWord.exe to load. I want it to load whatever is set to view these files in Windows. Is there a way to do this?
>
>Pete