IDEFix is a suite of programs, the main two being IDefix and loadide. CacheCDFS is also included and as you guessed is a CDROM driver.
IDEFix and Loadide do roughly the same job. (IIRC loadide makes idefix resident!!)
all you need to have is something like C:idefix (if idefix is in your c dir) in your SS.
Depeding on your confiuration there are a number of arguements you can add to the end of the command.
I suggest you throughly read the idefix instructions as it is all explained there.
Lewis