1.What overdrives do you have for your people?
All of them.

2.Did it take 4ever 2 get wakka's overdrives?
I got so annoyed with the sheer monotony of Blitzball that I stopped playing the game for about two weeks.

3.Jus talk bout them an ur favorite ones!
Rikku's are particularly useful. If you can find a way to get her to Overdrive constantly, consider yourself immortal. Wakka and Tidus pretty much do more damage than anyone else with theirs, so the three of them make a pretty solid team once everyone completes the Sphere Grid.