I have two answers for you. If you are using Windows, you may download using html, or with a windows version of wget (highly recommended). Once you have the iso file, you may burn a cd or dvd, (depending on what you downloaded), and boot from that item.
If you are already a Linux user, install wget (if not installed), use it to download the iso image of choice.
You may download the torrent file, and using the torrent protocol and your favourite torrent program (transmission is a good one for Linux), you download the ISO file.
Here is the address you need to fetch the one(s) you want.