iMac slowing down

My G5 iMac is now slowing down, I've had it from when they were first available so it is quite elderly as computers go. What can I do to speed things up? I seem to remember in the 'old days' we had programs that helped to sort out fragmentation - is that something I need to worry about?
Your advice and assistance will be greatly appreciated.
Roger

What are the specs on that old iMac G5? CPU Speed? RAM? Version of OSX?

Is it just a bit sluggish? Does it otherwise work well except for the slow down? No Kernel Panics?

One of the first things I would do is download and run Onyx and run all the maintenance scripts and optimization.

She is a 2GHz Power PC G5 with 1.5 GB DDR SRAM and running OSX 10.4.11
When you mention Onyx, scripts and optimisation I'm afraid you're speaking a foreign language to me, I'm merely an old fashioned, and aged, longcase/grandfather clockmaker.

In my last reply I forgot to answer some of your questions regarding her sluggishness. I don't know what kernal panics are but really she is just slow at starting an application or changing applications and loading things generally; it is as if she's trying to juggle the space to fit.
Roger

Download Onyx - the Tiger version - and yes the site is French - the app is in English when installed.

Once downloaded, open it - go to the Automation tab - check everything in the Maintenance and cleaning sections and let it do it's thing.

Also, do a Get Info on your hard drive - what size is the drive and how much free space is available?

The hard drive is 232.86 GB with 103.02 GB available and 129.84 used.

Should be good just running Onyx - still have plenty of free space.

Thanks guys, she's running better now, far less turgid. How often should I run the Onyx thing?

I try to remember to run it once a week, but sometimes go for a month at a time.