Winpup?

I have used AdAware, and Spybot S&D (along with Norton Internet Security Professional). I still randomly get re directed to a rather graphic pornographic search engine. (Not fun when the in-laws are over!) There is an error during S&D that is written as a warning in German, but mentions "winpup32" and that it can not be removed. I am assuming this is the cause for my problems. Also (related to this?) when I type in an address into the address bar I can NOT type in the "www" part. Doing so causes the computer to look in Documents and Setttings, and I get a "file not found error". Please help.