Items 5 and 6 do not apply to iSight iMacs because these are not user servicable except for adding RAM.
Resetting the SMU on a G5 iMac:
and on resetting the PMU on a Power Mac G5, G4 and G3 :
Brass, the ISight model does not have a back that just pops off! Thats why the disclaimer. Google "IMac I sight repair", lots of videos showing how to take an I Sight apart. I took my PPC I Sight apart to clean the dust out of it, I still use it on my network, but I dont recommend just anyone try this.