I need help with your fight against Jecht, I think his nickname is 'Braska's Final Aeon' or some thing. Anyways, last time i battled was with Tidus, Yuna, and Auron. Any strats that i could do with these or others?

You could try leveling up hardcore. I never recall actually having a hard time beating Jecht. I killed him with two turns I believe.

Cheap method. Acquire a chocobo at the Calm Lands and find a chocobo feather near the Macalania Woods entrance to the Calm Lands that lets you go to the Requiem Temple. Participate in the chocobo race there and open three of the treasure chests (I think that's the right number) without hitting any of the flags and you will get an item that Rikku can mix 2 of to make your characters always hit for 9999 damage. Use that and then let loose with Overdrives.