AFAIK, Office 2003 applications work as well as ever. Outlook is quite vulnerable, though.
When you say that hyperlinks change appearance, what do you mean?
Do you mean that they look something like this screen shot?
00 deleteme 1.png
If so, press
Alt+F9 to toggle display of fields. This is an application-wide option and stays the way you have it until you toggle it again.
Using Fields in Microsoft Word