Stored a few DVDs in plastic covers and stacked them upright. Now after a year when I reach out for those DVDs I find impressions of the plastic cover on them and it is making it difficult for the player to read them.

Tried home remedies to clean the DVD surface with little improvement, please recommend a cleaning solution to remove these plastic imprints from the DVD surface.

What do you mean "plastic cover"? I assume, for some reason, you didn't store them in the original keepcase. Do you mean a sleeve of some kind? And by stacking them upright, do you actually mean horizontally in a stack, so weight was pressed against them?

"I'm sorry, I don't do impressions. My training is in psychiatry."

Try boiling water

Yes, I had stacked the DVDs horizontally in plastic sleeves to save space and now they carry the impressions of the cover.

A customer of mine kept all his software CD-ROMS in a binder and that happened to a few of them. I think it's more of a chemical reaction than a stain. You'd think they would take this into consideration before they sell stuff like that as storage for media. It shouldn't affect playability so you're probably better off leaving them alone, rather than risking damaging them with a powerful solvent. Alcohol or boiling water might be worth a try, but test it first on one you don't care too much about or one that can be replaced cheaply.

Try boiling water.

Seriously.

Put the disc in boiling water, data side down, for 2-3 minutes. Wipe clean gently and try again. This won't damage the disc or artwork. Seriously.