How do I format HDD after installing new HDD?

What version of OS X came pre-installed on the computer when it was new. If it was Snow Leopard or earlier you can call AppleCare and order a replacement set of install discs from Apple for a moderate cost or you can order a copy of SL from Apple's website, at:

http://store.apple.com/us/product/MC573Z/A/mac-os-x-106-snow-leopardfor $20.00

Also if the machine is a 2009 or later the HD's that Apple used came with integrated temp sensors, most off the shelf HD's don't have that so you need to find a solution or the machine will overheat.

Five ways to eject a stuck CD or DVD from the optical drive

Ejecting the stuck disc can usually be done in one of the following ways:

1. Restart the computer and after the chime press and hold down the

left mouse button until the disc ejects.

2. Press the Eject button on your keyboard.

3. Click on the Eject button in the menubar.

4. Press COMMAND-E.

5. If none of the above work try this: Open the Terminal application in

your Utilities folder. At the prompt enter or paste the following:

/usr/bin/drutil eject

If this fails then try this:

Boot the computer into Single-user Mode. At the prompt enter the same command as used above. To restart the computer enter "reboot" at the prompt without quotes.

if you have a mac OS installation flash drive (USB memory stick) you could do it that way.

start up with the option key pressed then select the flash drive as the source for the set up - it then does the rest.

if you don't have one, get another mac user to make one on their mac - mavericks has an app for it somewhere. takes a while to write it (some hours) and you need a minimum of 8GB on the stick.

worked for me when i put a new SSD into my 17" MBP, no hassles - the machine had been running snow leopard 10.6 when and i put mavericks 10.9.4 on and restored everything from a Time Machine external HD. I was very pleased at how easy it was.

using the Apple bluetooth keyboard for the startup disk, it may be worth turning the keyboard off and on to reset it before you start.

Apple Wireless Keyboards: Using startup keys

if the DVD is in the drive the key you need is the c key to boot from that DVD.

Startup key combinations for Intel-based Macs

i might be wrong here - but isn't there a hole to poke with a pin on the iMac to eject disks? or can you open the case of the iMac and find a way to manually eject the optical drive?

saw this ... http://www.ehow.com/how_8130351_force-eject-disc-imac.html

Of course it can. The keyboard and mouse are pre-paired with the iMac when new. The computer specifically looks for the keyboard at startup so you can use the various keyboard shortcuts at startup.

No, I do not know about the jumper. Ask WD tech support.

Did you try using the c key to load the OS from the DVD as per those instruction in the link? that should give you access to disk utility from the DVD to partition the new HDD then load the OS onto the the new HDD.