If a movie says aspect ratio: 1.78:1. then it is full widescreen.
If a movie says aspect ratio: 2.40:1, then it will have black bars.
Most blu-rays & DVDs are 2:40:1 aspect ratio. (black bars on the top & bottom)
99% of everything shown on broadcast & cable TV is 1:78:1.
Movies that were originally 2:40:1 that are shown on TV are usually cropped/zoomed in to remove the black bars.
for that matter, every HDTV has some sort of zoom feature, that lets zoom in on the...