Can anyone recommend a good photo editor?

We'd like to find out if it's possible to make some edits to some of the wedding photos we've had back, both from our professional photographer and our guests - things like making blurry photos clearer and more in focus, doing face swaps in group photos to get ones where everyone is smiling and no one is blinking or gurning like an idiot etc. Maybe changing up the lighting/tone in some of the indoor photos as well. I don't know much about photo editing, so don't know what's possible, but would like to find out. Thanks!