When i download a part i could not open it and the name is something.rar and i can't open it with SW?
Download WinRar from here. http://download.cnet.com/WinRAR-32-bit/3000-2250_4-10007677.html
Install It. After installing follow these steps.
After installing winrar you can notice the change in icon of the rar file. Now right click that file and select extract to .
Some process will start and will end after few seconds and a folder will appear. Double click this folder and you can find all the files.