The straight Zip should work, but Windows won't be able to open it so you will need another unzip program like 7zip or winrar.
The heck do you mean? On Vista and XP I've been able to open .zip files just fine without any special programs. And Windows 7 does it just fine too. .rar files on the other hand, I've needed other programs on XP and Vista, but dad says 7 can do .rars on it's own.
For the record, it's now fully downloaded, unzipped (file>extract all files in the explorer window :p), installed, and patched. Ready to go for tomorrow