What? Final Fantasy VII? You mean there's something besides Advent Children? Snarky comments aside, you get to fight Reno several times in the game, and each time he's not that difficult. He uses some weird lightning rod-stick-thing to fight, and it can hurt, but not so bad.
Fight Number One
Reno has two attacks- his Electo-rod which does around 60 damage and can randomly paralyze, and a pyramid attack which imprisons your characters. Attack the pyramid with a physical attack and it will break. After that, it's not a very tough fight. Three against one is hardly fair. (And you're supposed to be the good guys!)
Fight Number Two
Win: Fairy Tale
This is more or less a straight battle. Which item you get from the Turks depends on which one you KO first. I reccomend focusing on Reno (as much as it pains me) because "Fairy Tale" is a good weapon for Aeris and you can find X-Potions lying about everywhere. Interestingly enough, Reno has lost his lightning resistance in this battle. Also, Rude cures and will never use fire on Tifa, and avoids attacking her at all if he can help it. how sweet.
Fight Number Three
Steal: Tough Ring
Again, Rude avoids attacking Tifa. This time around, Reno has a confusion attack and a powerful lightning attack. Rude has fire-based attacks, but none of them are resistant to either element. This is an optional battle, but it's worth it for the great items you can steal.
Fight Number Four
Steal: Touph Ring
Steal: Minerva Band
Reno absorbs lightning, Rude absorbs fire, and Elena absorbs ice- so it's best to avoid an elemental spell and the all materia for this battle, because chances are it will heal one of them. Elena can confuse your party, so watch out. This, too, is an optional fight, be sure to steal from them all.