www.7-zip.org - free and open-source
Install it, and then Right-Click the .ZIP file > 7Zip > Extract to "FolderName\"
That will unzip it to a new folder, in the same directory, with the same name as the original zip file.
For your own use, when compressing things like hand history text files, use the default .7z compression, as it will compress at a much better rate.
