That seems to be the correct file and size. Extensions may be hidden in your folder options, so you wont see xxxx.exe. Turn it on and make sure its an .exe. Are you sure you downloaded the file completely, it may be corrupted if the download wasn't complete. It will probably still show the file size even though its incomplete. The safest download in my opinion is the torrent (mirror 1). If you know how torrents work give it a try, and if that doesn't work, theres something strange going on.