This is embarassing, but my husband is in Afghanistan for a year and I picked up our C280 yesterday at the factory, and I'm unsure about how to drive it.
There is a C(comfort) and S(sport) mode to drive it, but I don't know what the difference is. The person at the factory didn't explain it very well. The book said to drive in C mode for the first 1000 miles, but the factory rep did not say that. What do I do?

C(comfort) is equivalent to W(winter). it starts with 2nd gear, you'll feel like it's lacking power. i'm not sure why do it on first ride. maybe just to adapt the driving style. just follow the owners manual it wont do no harm. great car! enjoy

Welcome to the forum and congratulations on the car.

In addition to starting in second gear, the transmission will shift a lower rpms when in C or comfort mode. You really should use this for the first 1000 miles or 1600 kilometers.