http://ftp.mozilla.org/pub/mozilla.org/b2g/nightly/latest-mozilla-central/ should work - for testing puroposes https://addons.mozilla.org/en-US/firefox/addon/firefox-os-simulator/

You can also try android on virtual box and flash it with Firefox OS but that is not likely to work well or at all.

hello, i don't think that mozilla has announced any plans to develop a operating system for desktops & laptops and personally i think it would be highly unlikely that such a direction would be taken.

at the moment the work done on firefox OS will reportedly focus to mobile devices (smartphones and tablets) only: http://thenextweb.com/asia/2013/06/03/foxconn-and-mozilla-are-collaborating-to-develop-5-devices-for-oems-including-a-tablet/

You might consider giving one of the entry-level linuxes a shot if you're looking for an alternative OS.

Ubuntu has spyware in it now, so I can't recommend that one.

Mint works pretty great out of the box, unzips things, browses the internet (Firefox is stock browser), plays flac, mp3, avi, whatever really.

Worth taking a look...if you have a USB drive kicking around you can try them as a live usb to see if you like them.

Check Windows control panel to see if you have a 32 bit or 64 bit Windows OS (Under System category).

Download Mint here: http://www.linuxmint.com/download.php

You can use LiLi to make a live usb, download here: http://www.linuxliveusb.com/en/download

Do *not* get the "no codec" versions unless you're sure you want them. It will save you some confusion if you're unsure.

Cinnamon is pretty nice out-of-the-box, I've never really liked MATE...ever.

This is a good linux distro to "cut your teeth on", and you don't have to be a 'nix wizard to make it work.

Hope this helps!