Software Deployment

I have Microsoft Office Small Business 2003. We have been using Word. We lost it. There is no icon. We did a Search and found it. We clicked it on. A window appeared and said 'Windows Installer" We watched it forever. We got tired watching it. We clicked cancel and a white screen appeared. It would not go away. We had to reboot. Still no word.
We recently installed NOrton 2007 INternet Security.
Help!