uh oh, this might sound like a sales pitch, but here goes:
Network ice or Languard are very good software firewalls. A report of who may ping a port, sniff for a trojan or anything is reported in detail (sometimes even being able to pick up the MAC address of the intruder). The log files generated can also be passed to ISP's who can then atke action against a user. Personally I think this kind of software is an absolute must if you have a DSL connection at home.
As for Virus scanners I really like Sophos, Vet & Antigen. Others are certainly good but it depends on your bias. Personally I find McAfee often flakes my system more often than I like, or others have a high over head on the system.
Sophos -
Antigen -
Vet -
I've used these on some large e-mail systems an all have worked very well (with Mail Marshall and Mail Sweeper). Vet you say? I heard of it through the British defense department security bulletins an it was very good. Its now owned and run by CA.
All are easy to use, and you can subscribe to alerts so you know whats going on and configure the scanners to update themselves so you've got excellent protection. In the work environment we do it daily or more, but at home you could do it once a week at least, or as often as you get alerts...
Something like system mechanic (iolo.com) is nice for keeping a system clean, and leaving no trail on your system (and being able to permanently delete things is nice too). I initially used it for cleaning my registry, but found it also placed a series of tools and options into one nice console.
Pest Patrol is simple, but works well and picks up on spyware, cookies planted when web surfing to monitor your patterns...
Hope that helps a bit, good luck.
John