I have that exact model running OS 10.2.8.
I had to hunt around on the FireFox web site but finally downloaded and set up version Firefox/1.5.0.1 for the Mac.
I tried the browser Opera at first but could not get to my Hotmail account, so then I tried this version of FireFox and it works great.
These liitle macs are great utilitarian notebooks but limited in what they can do because of there age. I use mine mainly as a lightweight travel notebook and also like the built in apps, especially iPhoto.
I have a new Toshiba laptop but prefer this little mac when using old fashioned dial-up via Net-Zero, as the Toshiba is a lot slower on dial up because of using Windows Vista, too much overhead (bloated operated system) on Vista for dial-up.
I am picking up an Apple 16 gb wi-fi iPad in a couple of weeks, and will use it when I want the high end cutting edge features for travel, but for any everyday inexpensive runner, the iBook is fine.
I also installed MSOffice for the Mac version 2004, and picked it up for around 60 bucks used at eBay.
Also it help to max out the RAM with a 512 mb simm card. Easy to install, the slot is below the removable keyboard.
Hope this helps.