[Edit: I see that the below question was answered while I was composing my reply.]
^ There's a lot of back and forth here and one of the posts might have answered this already, but what are you using for a display, IntelliVolume?
The one exception that comes to mind to Bob's comments about something being wrong with the TV setup if the thin letterboxes aren't seen on 1.85 movies would be rear projection TV's (such as the Mitsubishi DLP rear projection displays that were discontinued a few years ago) as these have inherent overscan to compensate for the screen and projector not being perfectly aligned. In this case, there's no oddball scaling going on that will mess with the image - pixels are just cropped by the edge of the screen on all 4 sides.
But any other fixed pixel display (plasma, LCD, OLED) should have a display mode that disables any overscan (some of these displays come from the factory with a mode enabled that has a small amount of overscan). When the modes that add overscan are used, the display is actually scaling the image to a slightly higher resolution and then discarding pixels on all 4 sides to get back to the native resolution of the display. This is undesirable as extra processing is involved that can reduce the quality of the image.
But as long as the geometry is correct (circles are circles rather than ovals and squares are squares rather than rectangles), that's the most important consideration. We don't want fat people looking skinny or skinny people looking fat.
Personally, I would hold off on a TV upgrade until the dust settles a bit more on 4K, HDR, and anything else the manufacturers decide to come up with to make their TV's fully compatible with UHD Blurays unless an upgrade is forced by the existing TV failing. I'm using a Mitsubishi RPTV that has non-defeatable overscan and have no plans to replace it for at least another year.