Has the Fireworks application EVER run correctly on your ibook? Is available RAM an issue here? I'm not sure that taking stuff off the "mainframe" is going to help your laptop computer, unless you are confusing the term.
Have recently added, or removed, anything from the iBook?
My Fireworks application will not open on my Mac OSX iBookG4. my computer is completely updated in software, is running flash and dreamweaver no problem. i tried taking all macromedia software off my mainframe (even the invisible macromedia files in fireworks and all the other applications too) and reinstalling, as well as running disk utilities. yet i always get the message that the program has unexpectedly quit. any ideas?