Well in some circles the term "Disaster Recovery" is no longer used and has been replaced by "Business Continuity". Which term you use does not matter.
The idea is that you need to come up with a plan to continue doing business when a "major" event occurs. You need to define the major event and what needs to be done. Some of the events may be specific and some generic.
Example: Why focus on Bird Flu pandemic? What happens if it is Bird Flu, but not a pandemic? What happens if it is another form of flu that is a pandemic, or some other contagious disease. What if it is only localized to your area or even your company?
You should always have a employee that can backup another employee. What happens one employees quits or dies?
You need to think about how long can your core computer systems run/stay up if nobody is there to "touch" them. Example: do you do tape backups to send off site? If so, what happens if nobody is there to take the tapes out?
Basic events:
1) Person that does a unique job is no longer able to do it (sick/dead/quit).
2) Building is in tact and computer systems are up and running , but people are not allowed to enter.
3) Building is in tact, but computer systems are down and will be for X number of hours/days. You need to come up with plans for say 1 hour outages, 4 hour outages, 8 hour, 24, 72, 1 week.
4) Building is not in tact.