Trim off the chewed up leaves and leave the healthy ones. The leaves are not going to "heal" and look nice again. The ragged pieces are doing nothing for the plant, and new ones grow pretty quickly if the plant is happy. Also, it will be easier to monitor the overall health of the plant if you can actually see what is going on. For instance (from the photo) it looks like you have some yellowing leaves, too.
I worked for years in garden centers and flower shops, and have cared for thousands of these plants. Sometimes we had to cut off up to 1/3 of the leaves if the stems got broken in shipping. Even if you cut off nearly all of the leaves, new ones will grow. (It just might take a while.)
I have also had friends give me near dead ones that I nursed back to health.
Here are links that may help you determine why your leaves are yellowing. (They also recommend snipping off the unsightly yellow or brown leaves.)
http://homeguides.sfgate.com/peace-lily-turning-yellow-64884.html
http://www.gardeningknowhow.com/houseplants/peace-lily/peace-lily-leaves-yellow-brown.htm
From your other post that you referred me to, I now understand that this plant is getting sunburned. Get it away from the windows and put it on a table, or even on the floor across the room. They like low, indirect light.
This site actually recommends 6 to 8 feet from a window. http://www.proplants.com/guide/peace-lily-care-guide