Player can toggle between original 4:3 or cropped pan-and-scan 16:9. The game uses pre-rendered backgrounds which are all stuck in 4:3.
In 16:9 aspect ratio, the 4:3 backgrounds are cropped and zoomed in with a camera pan added as the character moves higher and lower on the screen. Unfortunately, many areas are still cropped on the top or bottom in 16:9, so some way want to choose 4:3 original aspect ratio. FMVs and in-game cutscenes are also better in 16:9 mode (in 4:3 mode for in-game cutscenes, there is an unnecessary pillarbox on the left and right side).
While 4:3 mode is recommended for REmake, Zero is slightly more optimized for 16:9.
Use the Noise Filter Removal mod.