Game speed with Ati Radeon 2400 1012MB

[I want to play NOW!]

Okay I have tried searching but i can't really find anything that can relate to my problem. Alright so here are my Graphics cards details:
Name: Ati Radeon HD 2400
Chip type: Ati Radeon Graphics processor (0x94c3) <-- Not sure if this has any relevance.
internal dac (400Mhz)
and a 1012MB memory. I have a dell inspiron 530s so it's a vista.
And i'm a big noob atm. And everytime i try to start Zelda-windwalker it works fine but the
game speed is so slow! And it doesn't even show the whole game. The background is a black screen and there are lines flying everywhere.
Can anyone help on this issue?
Whatever you can offer will be much appreciated.

Domo Arigatoo

[HawaiianPunch]

What revision are you using? Post your CPU model, that's probably slowing you down. Try 3.0 with default settings and it will work fine.

[linkinworm]

if you're using an Ati Radeon 2400 1012MB my guess would be you dont have a very powerful cpu, wind waker should work fine with dolphin straight out the box without glitches though with DX9 enabled

[I want to play NOW!]

It's dolphin 3.0. Everything is on default but there are still problems with speed and gameplay.

[HawaiianPunch]

I will repeat. What is your CPU? What are your settings? Wind Waker should be fine out of the box like linkinworm said with decent hardware.

[I want to play NOW!]

Operating system: Windows vista Home premium (0.6, Build 6001)
Processor: Intel® Core™2 Duo CPU E4500 @ 2.20GHz (2 CPUs), ~2.2GHz
Memory: 2046MB RAM
BIOS: Phoenix - AwardBIOS v6.00PG
DirectX Version: DirectX 10
DxDiag Version: 6.00.6001.18000 32bit Unicode

[NaturalViolence]

Both the cpu and gpu are slightly too weak. If I recall an hd2400 is in-between an nvidia 8400gs and 8500gt.