Jimmunsw, you should check the SHA-1 hash of the file you downloaded against the one they provide next to the download link. I don't use windows, so I can't recommend a SHA-1 program, but Google gave me this one:
MD5 & SHA-1 Checksum Utility - Download.com
If the the SHA-1 hashes match, you don't need to download it again.
MD5 & SHA-1 Checksum Utility - Download.com
If the the SHA-1 hashes match, you don't need to download it again.