Illusive HDD hogs... Ibook G4 10.5.8

Bought an iBook G4 on ebay for around $100 bucks, free shipping too. Not bad IMHO. Works decent, does what I need (goes online while having an Apple logo on the back of the screen, lol).

Anyway, I the HDD is only 40GB, 37.xGB reported in disk utility (but that is understandable). The issue isn't the capacity, it is the available disk space. I have never been able to get over 16GB of free HDD space.

I have used apps like Disk Inventory X, OmniSweeper, etc etc, but after compressing and moving all of my 3rd party apps, my photos, music, videos, etc, all of the apps I mentioned above indicate that the hogs are in my Library and System folders. I know how to use the Mac OS, and since I bought my power mac G4 and this iBook, I have already bought a Mac Mini. The mini has snow leopard (I think, lol) and the G4 I installed OS9 (for classic gaming, classic mode sucks IMHO). I just don't know what files are safe to delete and really do not want to mess anything up, I have no Leo install disks at all.

Long question short:

If it isn't my apps and docs taking up 60% of my HDD, what is? I run daily, weekly and monthly maintenance scripts every day via terminal. I would normally just do a clean install, but not an option for me. Any ideas?

The one and ONLY thing I can safely recommend is that you search to see if there's anything like a "Previous Systems" folder. That folder -- and that folder alone -- is safe to throw out.

Apart from that, what's probably eating your disk space is swap files. You probably don't have the RAM maxed out which means the machine has to use lots and lot of disk space to run properly. This gets reset when you reboot, but it means the operation of the machine isn't optimal.