HOW do you unpartition a drive?!

Question

here's the situation; I got a new 500 gig hard drive installed in the eMac I got from my music teacher. BUT the computer center partitioned it into a 40 gig drive and a 460. What I wanted was a single larger hard drive. I was told that, if I started up from my Tiger DVD, chose "options" and erased the original disk, I would get rid of the partition. Not so. I did it and it didn't work.
What I'm doing instead is reinstalling OS X on the larger partition and making that one my boot drive. Will this work? I can keep the smaller partition as a fail-safe, I guess? But how do you get rid of a partition? What did I do wrong? For that matter, how do you add a partition if you should want an extra one? TIA!

Answer 1

"Disk Utility
1. Insert the Mac OS X Install disc that came with your computer, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
*Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.*
3. Click the Erase tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume, then chose MacOS Extended Journalled. Not the indented Partition.
6. Click Erase & look for Options. choose Zero 1 pass."