So, for the last week or so I have had no file listing in my save dialogue box in Windows 7:
Today I spent some time investigating what happened. I recall clicking on something too quickly while the dialogue box was opening and it went crazy from then onwards.
Rebooting didn’t fix it either.
However Process Monitor from Sysinternals allowed me to locate the cause of the corrupt layout and missing files pane:
Rename or delete the current user\software\microsoft\windows\currentversion\explorer\
cidsave\modules\globalsettings\sizer\commonitemdialogsizer key value
thecomputerperson 
Glad that someone found this and was helped by it :)
http://www.experts-exchange.com/Software/Office_Productivity/Office_Suites/MS_Office/Q_28672036.html
The above article was something I had first posted back in 2009 on another website and I migrated it over here when I changed blogging software.