Help to boot OSX from disc, using rEFIt

Hi all,

I have an older office iMac which is partitioned to run OSX and Windows using rEFIt to select the operating system.

I can access the computer using the Windows OS, but do not have the username or password for the OSX login.

In order to be able to use the iMac, I need to get access to the OSX system.
I have the OSX (iMac G5software discs and have tried pressing C and Option (Seperately) to boot from the disc, but each time rEFIt runs and I cannot boot from the disc. I have the options to run rEFIt Shell, Run Partioning Tool, or run an operating system.

Can anyone please suggest another way to boot from the OSX disc, so that I can restore settings or format the iMac and start from scratch?

 

That makes sense.
Just because a disc comes with the Mac doesn't mean that it belongs to it.
I need the correct OSX discs.

Thank you Darth.Titan