The best resolution varies from game to game, for older (and thus usually better performing) games you can choose a higher resolution than for the most recent games. It is not possible to name a general best resolution unfortunately.
You need to make sure that you still get a decent framerate (45fps+) when you change the resolution. Quality wise 1920×1440 is a good resolution, but with many newer games that may not be fast enough, so you need to find a compromise between quality and performance that works for your PC on a game to game basis.
Regarding RE7: as said in the other thread DO NOT change the resolution for this game, use the 1280×960 that vorpX suggests. If you can afford it performance wise, then change the multiplier in the game options like the message says that pops up when you start the game with vorpX.