newbie, how do I manage when my Norton Internet Security 2010 does auto log ins please read :

OK I just bought and installed Norton as mentioned and I am NO computer guru at all, but can i stop it from auto filling in my passwords?  and I'll take any advice. I think someone is " in my puter", and I want to be as secure as possible and if they are key logging,  I don't want them to have access to auto log in. I don't know if this makes sense, but I have a very smart evil neighbor and he KNOWS puters

 Here is an example of something else about security that maybe you can help me with, I had a yahoo address and it was connected to Yahoo Ask and Answer,  which I really enjoy, but all of a sudden, with nothing I did. it is now  posting with my avatar , by every question or answer was my FULL email addy. How in the heck did that happen ???????????????????

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