It depends on the context. If it's a battle of pure physical strength and chakra, Naruto might have the edge as he has years of experience and has faced more powerful foes. But Boruto has some unique abilities like his Jougan. So if the fight involves using new - age ninja techniques, Boruto could surprise Naruto.
It's really hard to say. Minato is extremely fast with his Flying Raijin and is a very intelligent fighter. But Naruto has an incredible amount of chakra, his Sage Mode, and his Six Paths powers. If Naruto can get close enough to Minato, his brute strength could overpower Minato. However, Minato's speed and strategic mind might keep Naruto at bay.
In some 'minato vs naruto fanfiction', there could be a scenario where they battle in a different dimension. Minato uses his Flying Raijin to quickly move around and Naruto counters with his shadow clones and massive Rasengan attacks. Also, a scenario where they fight not as enemies but in a friendly spar to teach Naruto some secret family jutsu that only Minato knew would be really cool.
Maybe a fanfic where Naruto and Boruto are pitted against each other in a virtual reality battle. It could be part of a training exercise that gets out of control, and they start using their real skills and emotions, leading to a intense and revealing fight.
There are many out there. A really good one might focus on the emotional reactions of Team Minato. For example, Minato might be proud of Naruto's strength and how he overcomes Pain. Kakashi could be in awe at Naruto's new techniques. Their reactions can enhance the overall viewing experience in the fanfiction.
It's really hard to say. Naruto has the power of the Nine - Tails and years of combat experience. But Boruto is young and full of surprises. He has his own unique skills. I think it could be a tie. They both have strong wills and would not want to seriously harm each other.
You can try looking on popular fanfiction websites like FanFiction.net or Archive of Our Own (AO3). They usually have a wide range of Naruto - related fanfictions, and you should be able to find some with the 'Team Minato Watches Naruto vs Pain' concept.
No, Boruto is alive in the manga. The plot hasn't led to his death. However, the manga is ongoing, and anything could happen in the later developments.