WinRaR?

I downoaded the Nodus client but when I looked at it, it's a folder and insdie the folder is only a .rar folder named minecraft. Inside the folder is a bunch of other folders like 'title' Help! I don't know if I did anything wront but what do you do with the folder or the winrar folder??? @Polo Help??

You are opening a jar file with winrar its not a problem, just place the minecraft.jar into you minecraft bin folder