The last time I checked, Zippyshare seemed pretty decent among other registration-free file sharing services. There is no countdown, the download page is as simple as it can get, the download button is so big that even if there is a fake one in one of the ads, it should be quite obvious which one to choose, and I don't remember having any popups either, just checked again in Iceweasel and Opera.

I can reupload the file if you point me to a better alternative.