First, go to System Preferences: CDs & DVDs (that's 10.4, might be named slightly different in 10.3 or earlier) and insure that the behavior for Photo CD is what you want. May as well do the rest now, so everything works the way you want when you insert disks, if you haven't already.
Then launch Image Capture and configure to you're liking as suggested already by adeptics: it determines what happens when cameras are attached to the computer. You will get a message saying something like "No Image Capture device connected." Ignore it.
Then make the choice at Image Capture: Preferences: General:
When a camera is connected, open : [whatever you want it to do]
Do the same for scanner preferences and check out the Sharing tab to be sure that works the way you want it to. Most people want this off, which will be the default. Then quit Image Capture and you're done.