For spyware I have used "Spybot Seach and Destroy" ... freeware

http://www.safer-networking.org/en/download/

I agree that Firefox is the better bet than IE

I have found MailWasher Pro 5.0 a good way to sort the spam from the mail I want. It learns which domains, email titles, and email addresses to blacklist. It sorts your "friends" and "probable spam" into serparate categories and makes it very easy to clean up mail downloads before importing via Outlook. It is avaiable for trial then a cheap purchase.

http://www.firetrust.com/

I will watch this thread for "shredders" since I have the same question.

Best of luck.