My iMac has been going very slow lately, certain programs lock up bad making it necessary to shut down the computer by physically pressing the power button. I think I've now determined that the internal 750GB HD has some bad sectors or something to that effect. I've tried to back up my iPhoto and iMovie libraries, but it always stops backing up in the same spot. I've had success copying things over folder by folder, but that's going to lose all of my folder structures, etc. I guess I just need to know what the best path forward from here is. I'm ready to purchase a new machine, but my top priority is to get all of my important family photos/videos off of this machine and to get this iMac fixed so it can be sold at some point. Any help in this regard would be much appreciated!