If you're running it from the live CD, its going to go pretty slow, since it has to go back and look up every single program that you run and such from the CD. You can install some things, such as plugins and save settings and documents, as long as you save them to a flash drive. This can make the live CD kind of handy, because by using the live CD and a flash drive you can run Ubuntu with all your settings on almost any computer. You can always run the live CD for a few days to see if you like it, and then change up the partitions later when you decide if you want Ubuntu or not.
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"Saying you love someone is not enough,
it's how you treat them that shows your true feelings." -Ryanne Mace