The options should not be "locked down."
Please check the properties of your /my documents/my games/elemental/prefs.ini file, and make sure it is not set to read-only.
You can manually open the prefs.ini file in notepad and near the top you will see entries for the screen resolution:
[Video]
DisplayWidth=1024
DisplayHeight=768
You can change this to your native resolution:
[Video]
DisplayWidth=1680
DisplayHeight=1050
and save the file.
Restart the Elemental game and you should now be running at your native resolution, and the options should not be in lock-down.
If the UI still looks messed up, please try changing the "Maximum Mip Map Levels" option to "1 Level" (you will need to restart the game) to see if that helps.
Please let us know how it goes.