sure can. Insert the cd, it should boot from the cd if not you need to enter the bios and select cdrom to make it the first boot device and the just follow the prompts.
Click the "User CP" button at the top of the forums, click "Edit Profile", scroll down to "Custom User Text:", type in what you want, and click "Submit Modifications".
You have to have so many posts before that option appears, but it looks like you've got enough.
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EDIT: Just noticed that you have already figured it out...