Only Square can rerender the backgrounds, providing they didn't delete the scene definitions after rendering them as they are now. Ironically, Square would have so little to do, to make an awesome FF7PC remake. They probably have the definitions for backgrounds and movies, right? Simply rerender them - movies at full 640x480 and backgrounds so, that a full 640x480 resolution area of any background would always be shown in-game. It would look awesome. Then, fix those few bugs (some gramatical and some graphical, like that Vincent model in the ancient's city that I mentioned in my first post

). Third, they should remake character models to a higher polygon count - perhaps the world models only (replace them with battle models?), battle models can be left alone (giving Square even less work

). And lastly, repair the game's code, so that it'll work perfectly on all Windows, including the newest. But it's important, that the game would otherwise stay as close to original as possible.
Four relatively simple steps, the bugs are probably widely known and could be pointed out by the FF7 community, only fixing the code could take a while - I don't know, with a giant like Square - maybe a month or two? Less?
In the end, they would have a (currently

) perfect version of a perfect game. I'd buy two immediately, hehe.