Very slow bootup

Welcome to Apple Discussions.

Try this, System Preferences, Startup Disk, Choose the internal Drive and restart.

Regards,

Roger

OK, let's try this. Put the CD that came with the machine in the SuperDrive and try to boot from it. Then run Disk Utility on the internal drive.

If you just did something like a system update (to install 10.6.2 for example), the subsequent start can take longer. So if there was some type of system-level installation, did you also give it "almost ten minutes" on the first and second attempts to start up?

The startup disk setting is in PRAM, so you can try resetting PRAM

http://support.apple.com/kb/HT1379

You can also try pressing and holding the Option key at startup to give you Startup Manager. See if the Mac OS X startup disk appears on the list. If it does, select it and continue.

Also try starting up in Safe Mode.

http://support.apple.com/kb/HT1455

Might be time to make an appointment at your local Apple Store to take it in. What were you doing with it just prior to this problem starting?

I know you already tried starting in Safe Mode but give it another try. Make sure you follow the instructions closely. They are;

1. Be sure the computer is shut down.
2. Press the power button.
3. Immediately after you hear the startup tone, hold the Shift key. The Shift key should be held as soon as possible after the startup tone but not before.
4. Release the Shift key when you see the gray Apple icon and the progress indicator (looks like a spinning gear).

Yup frustrating.

Let us know what Apple finds out for you.

but as the progress indicator went to about maybe 1/3 of the way

Progress indicator? Snow Leopard does not have the progress indicator anymore. Maybe the Safe Boot uses it, because it performs some maintenance. Let me try a Safe Boot (haven't done it since Snow Leopard)...

OK, the grayish Safe Mode progress bar must be for the maintenance it is doing when starting up in Safe Mode. So it stalls after that...

Did you try the Option key startup. Does that get you to Startup Manager? If so, insert your Mac OS X installation disc (for the currently installed system release) and it should appear as a startup option. Select it and attempt to continue the startup. If that works, that should get you to Installer's first screen. Go up to the menu bar and, under Utilities, select to run Disk Utility. Select the internal drive in the sidebar, and go to the +First Aid+ tab. Use +Repair Disk+. Don't use +Repair Disk Permissions+.

Since this is a new 21.5-inch iMac, that disc is the one that came with the iMac correct, not a retail Snow Leopard disc or any other disc? And it needs to be +Disc 1+, if it came with two discs.

It seems like there is some disk data or disk directory corruption on your Mac OS X startup volume. To go further, you need to be able to start up from the optical drive with the Mac OS X installation disc, which is not working for some reason.

If you cannot get it to boot off the optical drive, you'll have to have an Apple-certified technician look at it.