Office 2003 is in your profile.
Do you have the installation disk?
With Word, you could follow the instructions here:
My docs open in the wrong program! Re-registering Word using the commandline.
There are similar commands for the other programs. I do not know that it will help but it will not hurt.
It has been 10 years since I had a computer with Windows 8. Sorry.
When you double-click on an icon for a Word document (that looks like a folder) what happens?