I just checked again and there is a very slight*, clean black border around the picture's top, sides and bottom. So I put in a Blu-ray copy of Beetlejuice where the aspect ratio is listed as 1.85:1 and it, too, has the same border. I hadn't noticed the border before as I sit back some and the TV's bezel is black.
Doesn't seem to be what you described.
*maybe 3-4mm, tops, at its widest.
Thank you, so sounds like 2D Hugo fills your screen as best it can. I think we in the UK are being short-changed with the 2D/3D disc release.
I used 1.1 overscan and it fills the screen so is a workaround.