I maintain a simple 5 computer peer-to-peer network, with internet connection sharing, at work. All computers run WinXP. When I set up the network I installed a software firewall on the computer that makes the internet connection, installed the free AVG anti-virus on all computers and put AdAware on all computers. AVG is set to automatically scan once a day at 3:00 am, I run a scan with AdAware once a week.
In almost 3 years we've had NO viruses, NO spyware. I spend maybe 30 minutes a week doing the scans. That's it.
My computer at home has been virus and spyware free for the same period.
By installing 3 simple and free programs you can protect your computer completely.
I find that "elegant" enough.
Add Firefox and Thunderbird and you'll really be garbage-free.
If you want to go the full road, use Open Office instead of MS Office.
There is no room for common sense in this discussion. </ sarcasm >