Firefox downloads Hanging when 0 bytes are left
Whenever I attempt to download a file of any notable size from a file hosting service, the file will download normally until it has 0 bytes left, at which point the download's status becomes "unknown time remaining" and proceeds to hang for 10-30 minutes. It's unlikely that it has to do with the server, since this happens to files downloaded from a number of locations.
Opaite Mbohovái (3)
You're using a 3 year old version of Firefox, which isn't supported any longer.
http://www.mozilla.com/en-US/firefox/ or http://www.mozilla.com/en-US/firefox/all-older.html
This can be caused by anti-virus scanning software on your computer that prevents Firefox from finishing the download.
Try to disable your AV software during the download and the installation and start the installer via the right-click context menu and choose Run as: Administrator.
Considering every other version of Firefox is slow for browsing, your answer does nothing to convince me that updating to a newer version of Firefox is beneficial.