Ok, now lets do some TLC on the iMac.
First, do a pram reset, this works best using a USB type keyboard (any kind will do).
To do a PRAM reset, you need to restart your machine and hold down these 4 keys all together at the same time.
‘Option’, ‘Command (Cloverleaf or Apple)’, ‘R’ and 'P' all together at the same time.
Keep them down until you hear 4 startup chimes, this is the sound that your computer makes when it starts up, it is like a boonngg. The screen should also cycle from white to black and then back to white along with the chimes.
The sound should also get louder.
If you have a wireless keyboard then the procedure is a little bit different.
Use the very same keys but wait until the first chime and immediately press and hold those keys. I recommend getting your fingers ready because timing is critical.
It can take many try to get it, any USB keyboard is preferable.
Substitute the Control key for the Command key and Alt for Option, all others stay the same.
This resets all of the system buses on your computer, USB, FireWire, display, ethernet and your keyboard/mouse/trackpad.
This will correct many faults but not necessarily yours.
Now, once that is done, try iTunes and the iPhone again.
If that works then open iPhoto and see if it shows there also.
Let me know.