This may seem a bit back to front, but try doing a repair or renistall first as it seems that a file may have become corrupted. Long time since I used Office 97, but I think if you put the CD in, one of the options when it auto runs is to Repair Office Installation, if so choose that, if not try a reinstall over the top of the existing. Once you are done you may be able to uninstall it as the "initialisation file" (whatever that is!!) should have been fixed/replaced.
Failing that it means either finding utility somewhere or searching through the registry and deleting everything to do with Office 97 -- just make sure you back the registry up first!