iMac will not boot anything

I tried to restore it via time machine. Now when it starts up it gets to the blue screen and stays there. The factory installation disc is in the machine. I cant get that or anything to boot. and i cant get the CD out. What can I do? thanks

If you can get the machine to reboot, hold down the left mouse button to see if you can eject the DVD. Otherwise you can try the method given here.

Once the disk is removed, try booting with it again and instead of trying to restore from Time Machine, go to Utilities, Disk Utility, from the top menu, highlight the hard drive on the left side, and do a Verify and Repair.

Regards.

No good. I got the CD out but when i rebooted with it back in It still got stuck at the blue screen.

Just rebooted again and held down the option key and i choose to boot the cd and it looks like its booting ok so far so i should beable to do the verify and repair.

Durring verify it said it appears to be ok, then during the repair it said "Invalid Node Structure" Could not be verified completely, Error: Disc Utility cant repair this disk...disk and restore your backed up files. What now?