Re:How easy is it to get a buckled mountain bike wheel unbuckled?
I remember when we were kids we used to , erm , "fix" buckled wheels with hammers !! LOL !
I wouldn't recommend tightening spokes unless you know what you are doing in a wheelbuilding sense , IME tightens and loosening spoke in a haphazard fashion invariably leads to spokes breaking a few weeks later
Best bet would be to take it into a bike shop (a decent one) , and get them to do their best with it , OK so they may not get it 100% - but they'll get it true enough for V brakes , and most importantly it'll be stronger than if you simply guessed which spokes to tighten / loosen.
Lazy is a word used by the obsessed, to describe those with a life.