Busta999,
Well, from what you say I think the file is corrupt in some way that causes this permissions error.
One last thing I just thought of: Can you copy-paste the complete file name here? That may not be necessary because you could see for yourself if this video file began with a dot "." If it does begin with a dot, that can be removed by renaming the file.
As for logging in as Root User, you will want to look at this Apple Knowledge Base article for future reference whether or not you try it in the present.
http://support.apple.com/kb/HT1528
I'm glad you can replace that file.
But you say you're seeing other odd things... do you want to elaborate on that?