The fill in thing is called Auto Fill and is considered by many to be a help.
You don't have to accept what it puts in there, just keep typing. Autofill is specific to each program that uses it and needs to be turned off in that particular program.
What program is causing you annoyance?
Downloading usually refers to the act of bring a file down off the internet (or such place) onto your computer.
From what you are saying I guess you are trying to create (burn) a CD with your pictures on it. Is that so?
You know when you start to type something in a text field and it automatically brings up the thing you typed previously with the starting letters? How do you get that to stop? It's annoying.
Also, I can NOT download a CD that can be viewed on a PC from iphoto. I've tried everything!! Even when you export the photos into a different place... yeah it's not working. Any tips for me?