If I'm not a computer guy, how can I know my computer is clean?

[scott8]

I really want the security and the sanity of knowing there is nothing hiding somewhere on my computer.

I have Norton, I have spyware, but I'm sure there are programs that can get around this [censored].

I use PT, and PA, so I have stuff going on often.

I would take the time to root through files, but wouldn't know what to look for.

What can be recommended?

Lets say I have good reason to want to be thorough.

Thanks in advance,

SC