if you are 16X9 is the standard letterbox for most widescreen movies. Some are 16x9 and they will say on the back.

You should not see side bars unless watching standard (modified for your screen) 4x3...but you would be full top to bottom.

IOW, I'm leaning with the "crap" definition down below. I get the bars all around on some tv broadcasts..but standard zoom fills the screen with no cutoff.