Deleting 2 volumes on main HD

Hey guys and girls,
I need SERIOUS help.

I have been trying for days to do what I need done (which I will explain), so I need really really simple step by step answers, excluding technical language.

I brought a PowerBook G4. The previous user partitioned the HD into 2 parts - OSX and OSX 1. OSX = 30 gb and OSX 1 = 30 gb. All the system files and OSX 10.4 is on OSX 1. With App's I have added over the years, MY START UP DISK IS FULL. This is where my problem starts.

***I want to delete these two partitions, so the start up drive has the full 60gb capacity of my HD***

I cannot repartition the HD because its the boot up disk.

How the **** do I delete those two partitions. I dont care if I loose everything. I have backed most of the files and app's I have on an external HD.

So:

I have a PowerBook G4.
I understand and have browsed Disk Utility before.
I know that I cannot deleted or partition (reset to 1 partition) the main HD because it contains the boot system files.
I have an external HD.
I have the Mac OSX 10.4 Tiger DVD.

I appreciate your help, but please make easy to understand... im stupid.

Thanks
rrxer
([email protected])

*These directions will delete all partitions and prompt you to reinstall Tiger*

1. Insert Tiger Install Disk. Restart while holding down "C" to boot from it.
2. Once booted from the disk, check on the menu bar for "Utilities".
3. Pull down and select "Disk Utility".
4. Once opened, select the root hard disk (the icon should be a hard drive and on the top.)
5. Click the "Erase" tab.
6. Choose "Mac OS Extended (Journaled)" as the format.
7. Click "Erase" on the bottom and click "Yes" when it asks if you are sure.
8. Once formatted, you should be able to install Tiger from the disk as normal.

You should have the full hard drive with a base install of Tiger.

Cheers.