430 II will do the flashing bit. If you have a 600D or 60D you'll be able to use the camera as a master and trigger the 430 II as a slave as well.
The 430 II can't be a master itself (triggering other flashes) though. Moreover, the buttons and config things are quite annoying. The 580 has very nice tactile buttons while the 430 has soft buttons that require a deep nail press in order to operate. As a flash it does its job quite well, but it's just not very nice to use. If you get quickly annoyed over these things... Think twice about the 430 (and perhaps consider different-make flashes as cheaper alternatives to the 580).
I got a 60D with 430 II, and it's fun to play around with using my camera as a master with the flash set up as a slave somewhere. Works wonderfully, quite good enough for some experimentation. Could be more friendly to operate button-wise. And I won't be using it in the splashing rain (it's not water resistant, unlike its 580 bigger brother), so this is fine for me.