you didn't tell us your actual OS (and posting in the XP forum by Mac and Vista and Windows 7 users happens all the time), but ASSUMING you do indeed have Windows XP as your operating system you can simply use Windows Explorer or My Computer to browse to the downloaded ZIP file and double click it which unzips it for you.
I just read this statement , "simply unzip the downloaded file then.... How does one 'simply' unzip a file?In the past when i downloaded things i sometimes got a message saying the download needs to be unzipped.I didn't know what to do from there.Thank you.

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