Updating an older iMac using 10.3.9

I've just decided to reconnect to the Internet my iMac bought in 2004 after it's been largely unused for about 18-20 months (been using my newer, crappy work PC laptop instead). I've discovered there are lots of software upgrades and other things I can't do because of the outdated operating system, which is OS X 10.3.9. I need to get this to at least 10.4.9 to get the latest version of iTunes, which I need for my new iPod Touch. I'd like to get the most current operating system possible for this older machine. Does anyone know what that is? What do I have to do to get it? What will it cost? I spent quite a bit of time on the Apple site and Googling today but was unable to find exactly what I'm looking for. Any advice would be much appreciated!

You didn't mention the CPU speed of your iMac...which is important in determining what the latest OS version you can update to.

If the iMac CPU speed is 867mhz or less...than Mac OS 10.4.11 is the max OS you can use. If the CPU speed is equal to or greater than 867mhz...then you can update to OS 10.5.8.

In either case...to purchase an install DVD will cost you around $100-$125 dollars.

Best place to get it is probably e-Bay.

Good luck,

- Nick

Because that's a PPC machine, you're limited to Leopard (10.5). How fast it'll run is debatable, since your model of G5 iMac is limited to a 1.8 GHz processor. You will need to purchase a retail version of Leopard. Maximum RAM of 2 Gb will help your cause.

Cost? Check the auction sites, like eBay, Amazon, or this M-F site > Buy/Sell/Trade. Best place to buy RAM for Mac is OWC Performance Upgrades; FireWire USB SATA Storage; Memory, more at OWC.

The best resource for finding out all about your model of Mac is Mactracker.

Others have reported buying Leopard from Apple by phone order. It's not available at the brick and mortar or online Store.