Can't install nor try ubuntu 12.10, system halted

Question

tried to find a solution but I wasn't able so far.

I downloaded the torrent version of ubuntu 12.10 and burned it onto a dvd and created a bootable stick using unetbootin... the thing is, when restarting my computer won't recognize the dvd (the optical drive DOES read dvds...) and booting from cd works fine.

Trying to install it from the usb stick I get a black screen with a blue square labeled "unetbootin" and it seems like it wants to install, but I get "uncompression error - system halted" before it gets past the second text line. Any suggestion? My computer ran 12.04 just fine and I'm using Mint 11 as a temporary solution

Solution

Actually, I solved it...
Had to download the ISO file again and create a bootable USB disk using the default bootable disk creator tool (used unetbootin last time).
When I had 12.04 running, it wouldn't accept my previous ISO file.
I don't know what changed, but the new ISO file was read well and I installed it that way.