I want to install Cuda but don't know how?

Hi, sorry if the post don’t come here, I have windows 7 an a evga geforce gt240 ddr5 1gb, in the box say’s that support CUDA, so I wanna try, but like I’m new in this, I don’t know where to download CUDA.
I search in the drivers download and the result was GeForce/ION Driver v266.58, I have to download this to get CUDA? I saw this page too CUDA Toolkit 3.2 Downloads | NVIDIA Developer . It’s this CUDA Toolkit that I have to download to get cuda.
Sorry for asking but really this is my first graphic card, so thats why I’m asking, hope someone can help me.
thanks in advance