I know there are a number of threads on this issue, and a number of causes for it. But basically, my husband's mac book started acting weird while I was out own town. He was unable to get it to start up, but eventually did, backed up his important data, and then I had him attempt to verify and repair permissions. I guess it indicated there were errors but could not fix them. Once again, his mac book stalls at start up and will not get past the gray screen with the apple and the wheel. Last night at this point it kernel panicked. Today ( since I'm back now ) I tried to boot it in safe mode, and it still hangs. I zapped the PRAM, and that didn't help. My next step is to try and boot from his install discs, when he finds them. My question is, should I bother trying to verify and repair, or should I just do an archive & install (if possible) or an erase and install (if necessary)? Any other thoughts or ideas are helpful! This is a mac book from 06-ish running 10.4.? My hubby claims to not have installed or updated anything recently.