Re: I try to avoid the seedier portions on the 'net
ad aware and some others conflict with some anti virus programs due to the way they quarantine files I think. There are workarounds or you can use programs recommended by Macafee.
I think Webroot (free with a MSN hotmail account)) will work with Macafee.
Is your firefox popup blocker turned on? You will find it under tools/options/content. I went to msnbc and firefox immediately blocked a popup.
I didn't see much on that list worth fooling with.