How do I keep a hot meal fresh for several hours? In three days, I will be picking up two fully-prepared chicken dinners - with potatoes, cole slaw, and a pre-packaged dessert - from work to home for my wife and I.  I've done this before and it came out fairly well.  

The problem is, I know for a fact that I will have to keep these dinners, which are cooked on-site shortly before pickup, in my office from 1pm to 5pm, and take them home on the bus, which could on a bad day mean that I won't be home with them until 6pm - a full 5 hours of sitting out at room temperature (or outdoor temperature, whatever that might wind up being in springtime).  

I know that we can make these meals warm again in the oven or microwave, and that the Styrofoam container they'll be in will help too, but are they safe to eat after sitting out for such a long time?  And is there any superior way to transport them to eliminate spoilage?
Refrigeration! They should be cooled to refrigeration temperature as soon as possible after pick up.  You can do this in a cooler with ice, if you don't have a refrigerator.  A portable cooler will allow you to take the dinners home on the bus.