The UI to the content repository is not really of much general use. The content repository is primarily meant to be a utility package that other packages use to store content, and one normally views such content through client packages rather than through the CR itself.
You might, for instance, play with packages like file storage or the photo album package. These both create content in the CR. Typically, though, you'd visit "your.site/file-storage" to look at files rather than the generic CR UI.
There's some messiness here due to some integration work by ArsDigita that was never completed (the CMS originally was designed as a standalone system, and the Content Repository is a generalized storage utility for ACS 4 that implemented a bunch of the CMS's storage datamodel and API when it was decided to integrated the CMS with ACS 4).
The CMS has the ability to publish content to the filesystem to avoid the overhead of database lookups, but this functionality hasn't been exposed in a way that's useful for other clients of the CR.
Cleaning up some of the basic CR and CMS functionality is one of the more important goals I have in mind for 4.7 ...
For now, though, you'll have better luck using the UI provided by client packages themselves rather than the generalized UI provided by the CR.
If you're interested in digging into this stuff and lending a hand for 4.7, we're always looking for volunteers!