If there's no widescreen left, I WAIT until there is. I under no circumstances will accept a film that has had half of its image cut off. Fullscreen is not acceptable in the least.
I remember Empire Strikes Back demonstrates a great example of widescreen's clear advantage. During the scene when Vader is pursuing the Falcon through the asteroid belt, an asteroid hits another Star Destroyer. You see the Captain in a holigram in the background on Vader's ship, and you see him react to his ship being hit and then his holigram disappears.