RNE, you need to change your daily procedure
use drive 1 for work files, use drive 2 for a back up, and back up your work files daily.
burn a CD at least once a week if not more often, every several days.
Store weekly backups in another building or your car.
Given that 200 mile drive, I assume you already are using a battery backup UPS with a heavy duty surge protector in front of it.
finally, you might want to consider buying/building a cheap mule to connect to the internet, and leave your work computer entirely physically isolated fom it.
Since word is not a common format on the net, I assume you recieved the original worm either in an attachment or by physical disk.
Why didn't you scan it when it first came in?
finally, consider getting a Mac.
end of lecture