i think that is the A/C condenser. it is in the very front of the car in front of the radiator. I looked up a picture online and thats what it looks like.

 

 

^that picture isn't right, that's an EP (civic Si). It has a K-series and as a result the A/C is on the opposite side because the engine is turned around 180º, making the drive belts on the passenger side of the car. His car has the condenser on the driver side.

 

Actually his 2003 EX would have a full-width condenser in front of the radiator. The half width side by side configuration was used from 1992 to 2000 (at least for non-Si models).

A dented radiator should be OK as long as not leaking. If it's real bad and looks like its about to crack, certainly consider replacement.