Yes. FXAA is very fast, but doesn't look very good. SSAA is very slow and uses a lot of resources, but gives the best visual quality.
And yes. If you have 1080p, stay at 3x max. I think 4k is 4 or 5x. I don't remember off the top of my head. Dolphin's configuration interface should tell you.
Ansiotropic Filtering should be fine to set at 16x. There are some games that glitch out at any setting over 1x, but those are documented in the Dolphin wiki if a game has AF glitches.
Post processing is just filters. You can ignore that. (I think FXAA exists in that selection, but whatever)
And yes. If you have 1080p, stay at 3x max. I think 4k is 4 or 5x. I don't remember off the top of my head. Dolphin's configuration interface should tell you.
Ansiotropic Filtering should be fine to set at 16x. There are some games that glitch out at any setting over 1x, but those are documented in the Dolphin wiki if a game has AF glitches.
Post processing is just filters. You can ignore that. (I think FXAA exists in that selection, but whatever)