Prepping my iMac G5 for sale

[Dew9993]

I'm getting a new MacBook Pro and am planning on selling my iMac G5. My question concerns restoring the machine for sale. I want to get rid of all my files and programs and such that I've added over the years, but the problem is I want to keep the OS up-to-date. I think I purchased it with 10.3 installed, and now have 10.5.5 on there. I don't want to use the restore disk and risk reverting it back another 2 generations. Any advice?

Thanks for the replies guys. Problem is, I don't have the 10.5 disc (used a friend's family pack). Is there any way I can find it online or something? Maybe bring it into the store?

 

[scienide09]

Back up your files and whatever else you need.
Boot from your OS X 10.5 (Leopard) install disc.
Instead of installing right away, open Disk Utility (from the install disc).
Erase and reformat the drive (writing zeroes will do you good, 7-pass is way more secure).
Install 10.5 from your disc.

 

[Makosuke]

What scienide09 said, although doing a 7-pass erase will take a long time and is completely unnecessary overkill--a single "write zeros" erase is plenty for security purposes.

And frankly, just doing an "erase and install" should be enough if there isn't any sensitive data on the computer. I'd probably do the all-zeros pass just to be safe, though.