installing from usb stick.

[ArtificialDream]

I downloaded an Ubuntu 8.10 and used unetbootin so that I could install it from a thumbdrive. The problem arises when i choose my usb as boot device, a unetbootin interface shows up with 3 lines: default, help and oem. There's also a 'press tab to change options'. When I choose default, it shows 'Loading /ubnkern...' and after that it goes straight to the desktop that is not usable (freezes). Is my copy a live cd? I got my copy from a torrent site. I searched for installation guides and the first thing that should welcome me is a language selection menu, but this doesn't happen, any help?

Thanks in advance.