Zip file download, will it ever stop?

This may seem like a stupid question, computer downloads aren't my strong point, but I still need an answer.My computer (a mac from around 2005 if it happens to matter) is currently download a zip file. I have downloaded it before so I think it will work but for the past 20 minutes it has just said, while still downloading, decompressing the zip file. Will it ever stop or is it not going to work? How long should it take? http://www.thestereophones.com/main The whole album is the one being downloaded. :/