The Ultimate Boot CD that came with the Freespire and Ubuntu has a lot of helpful hardware but wouldn't boot using my F9 option to choose the boot medium. It did boot using the older method of entering BIOS and setting CDROM as the first boot device.
Ubuntu - The installed version may be great, but the Live CD is less versatile than a Knoppix Live CD. If wanting just to run a Live CD, download Knoppix instead and burn the ISO disc image onto a CD you've also made bootable. Unbuntu's greatest deficiency as I see it for a Live CD is lack of ability to play many different video and sound codecs. In fact it may only play wave files in the Live CD use, I got tired of looking for others it would play. It will give a screen however to download and install the appropriate codec, which is great if you have it installed on the hard drive, but not sufficient for a Live CD version.
Freespire - Also less than Knoppix for a Live CD, and less than Ubuntu too. Too add to frustation for many will be it's username and password prompt. You'd think anything should work in there if it's a Live CD, or even more you'd not even expect to encounter it at all. Oh, but no, there is a procedure you must follow. Is this procedure on the disc in some text or doc file? Again, no! I found out how to access it after some concentrated googling. To do it, once I hit that part, I had to do CTRL-ALT-F4, at the login type "root" (without quotes), issue passwd command, change the password to anything else, confirm it, press Enter key. Then it took CTRL-ALT-F7 to return to the GUI and enter those values on the login screen. Finally you get the Freespire Live CD to run it's programs.
Again, go with Knoppix if you are looking for an easy to use Live CD version.