Install and Use Ubuntu first. After you use it for some time and are comfortable with it, you can migrate to any other distro. Its no big deal. IMHO you should have ubuntu as your first distro. Getting help for ubuntu is very easy. Most of the guides in the web are for ubuntu. So, its better to start with ubuntu. Then after a few months when you have that feeling of want to know more then go for redhat or fedora or suse. After few months of fedora and installing half a dozen more distros you will have another feeling of wanting to go further. Then install Arch Linux. A few years after that you will start compiling your own kernel and maybe start your own distro. At that time dont forget to mail me a copy of your distro
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