Dual Source

From My Question of Vista Earlier, should I dual boot to Linux, and keep XP? Is Ubuntu a good OS to dual boot?
Is Ubuntu a good choice if I want to dual boot, If so, is it even worth the trouble? Remember, I cannot download any software from the built-in download app, I must download it from another source (I would like to use ONLY the ubuntu site to download apps).
I think that ubuntu is a good thing, but don’t know if the Desktop CD takes over the partitions, or if it just makes a new partition. I also don’t know what kind of compatitibility there is. If you could answer all these questions, and comment back with detail it would be nice.
THX.
it sounds like your going to run linux from a live disc, that has no effect on your harddrive or partitions, if you want to make changes to the software just run it with a usb drive, it will auto maticly save the info
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