Our iMac (iMac 8.1, purchased about 1 1/2 year ago, running the latest update of MacOS 10.5) started to act strange (slow response, lots of waiting etc.) a while ago, but I blamed my wife for having too many icons on the desktop and too many open tabs in Firefox. However, things turned to the worse the other day, becoming almost completely unresponsive (the mouse pointer can be moved, but icons on the desktop and the Finder menu-bar appears after several minutes since the dock has appeared). At first I thought it was Spotlight indexing, after having its index files damaged or something, so I made it re-index and left the computer on all night, but that didn't help. I also tried checking what's hogging the computer by running "Activity monitor", but of course that application (like all other apps) take about 5 minutes to start after clicking the dock icon, so when it finally runs whatever has been hogging the iMac is done. I've also tried booting from the system DVD, then running disk utility to check the drive (no reported problems) and checking/repairing permissions (this does tell me some permissions needed to be fixed, but unfortunately didn't help after rebooting). I've also tried to "archive and reinstall" the operating system with no improvement. What else can I try? I would think completely wiping the drive and reinstalling everything from scratch would do the trick, but that would leave me with a lot of work putting personal stuff I want to keep back into their right places (email (Apple Mail), bookmarks, passwords and web history (Firefox and Safari), Address book entries etc.). I have an external Firewire drive connected to the iMac which does Time Machine backups regularly, so I shouldn't risk losing anything, but just restoring from that drive could mean I'd just put the problems back in, wouldn't it? Finally I tried creating a new user, to see if the problem lies within the user folder, but right now I can't even change to that user because the iMac boots directly into the regular user and there's no response when clicking on stuff. If the iMac does start responding I'll go into the "Accounts" system preference, turn off automatic login, reboot and log into that fresh, new user and see what happens. Until then, what do you guys think is the reason behind all of this, and what should I do?