My Files are all classified as "Other" In Finder, every single file on my disk is classified under the "Other" section.  However, when I go to "about this Mac", it shows only  a fraction of my disk is actually "Other".

How do I fix this?  And does this have any other harmful consequences?

I have tried clearing the NVRAM and PRAM. I've tried rebooting and deleting the Finder preferences. I've updated Mac OS X.  None of those fixed it.

Edit: this only happens with my account so it probably can't be anything wrong with CoreServices. Maybe a messed up setting?

Here's an example screenshot of how things look:
In this particular instance All My Files are being exclusively sorted by Tags. The problem here is that this is not exactly obvious or apparent. There are several ways to adjust how files are arranged or sorted in Finder. I find one of the easiest and most convenient ways is to:


  Control + Mouse Click within the window or heading.


(In this case control-clicking Show All in the right corner). 

Control Mouse Clicking the inside the window or heading above the files should reveal a menu that shows the options View, Arrange By, and View Options. From there select whichever criteria you might prefer files Arrange By - (Name, Kind, Application, etc). 

One thing to note is that within View Options you can choose to Sort By instead of Arrange By, or even both; this can lead to some confusion in itself (which is briefly touched upon here).

The Control and Option keys while mouse clicking within Finder windows can reveal options and menus that directly affect what appears — don't hesitate to discover what's there.