Problem may be resolved
I was able to install by running the installs under safemode. I have not used the extensions yet, but they appear to be correctly installed. I will post back in if any problems persist.
To answer the questions, yes i accessed the correct folder its the only user on the pc. The CS4 is the only product version that has been installed and on a clean copy of vista (I recently redid the station a few months back). There are no conflicting installations of adobe products. (Clean vista and adobe creative suite installs).