What would you like to run? LiPo, NiCD, NiMH? NiMH is great for starters. NiMH can handle more MaH then a NiCD. NiCD's also have memory loss, and NiMH don't. NiCD also needs to be discharged once and a while.
If you really want to crazy, you can go LiPo. LiPo is very light and lasts longer than an NiMH pack with the same MaH rating. But LiPo's are very dangerous. If overcharged/false peaked or mishandled, they will explode on you.
ok thanks i am going to go lipo 3c battery i have herd a lot of good things adout them and the warnings to but wat battery would run good plus a really fast charger