Accessing 16:10 resolutions on Mac Mini?

So let me see if I understand completely. You usually connect your Mac mini to a 1680 x 1050 monitor. You usually run the monitor at 1280 x 800. You have two such monitors (are they identical?) , but you must be only using one with the mini at-a-time, right? Then you hooked up a TV to the mini and now when you go back and hook up the monitor(s) you don't see any choices for 16:10 resolutions.

If that is accurate, it could be that the preferences file(s) for displays has become corrupted. Try the following:

Starting from the hard drive icon in the Finder, in /Library/Preferences there should be a file labeled com.apple.windowserver.plist. Throw it in the trash or else move it to an alternate location, like a newly created folder on the desktop. Also, for however many user accounts are on the mini, there should be files in /Users/name/Library/Preferences/ByHost that are labeled com.apple.windowserver.xxxxxxx.plist where xxxxxx is a string of letters and numbers and where name is the name on the account. Move all of those files to the same temporary alternate location as well, or else throw them in the trash, then restart the mini.

When OS X restarts and finds those files missing from their expected location, it will generate fresh copies with factory default values. That should give the mini a fresh start with any display attached to it and hopefully things will start working normally and as expected.