Mac OSX CD Re-Install

I have a Power Mac tower, and the hard drive crashed. I bought a new hard drive, and I'm looking for some help with reinstalling the operating system. I have the Max OSX 10.4 CD, but my issues is how do I get the CD door to open at power up. Can somebody give me a hand with how to get the CD door to open at power up, how to boot from the CD, and how to format the new drive and install the OS on the new drive? Thanks.

this isn't about Mac Pro as the title indicated...

Didn't know there were such militant rules on titles and topics. Thanks for your constructive help!

You can hold down the mouse button on startup to open

open cd drive

try either the F12 button on the keyboard or manually open the external cd door cover and press the eject button just under the cd drive tray. Hope it work for you.

From your description do you have a MDD model with the shiny front. If so boot up, press the eject media button top extreme right of keyboard, pop in the Tiger Dvd, reboot and as soon as chimes hold down 'C'.

When the disc commences choose 'erase and install' from options and it will erase the drive and do a clean installation. Trust this is what you asked for?