Menu Bar Disappears when I close an app

Under the circumstances, troubleshooting the status of the rest of that iBook G4's hardware

can be difficult; some examples had issues with logic boards that can exhibit odd effects.

That model portable should have had enough RAM affixed to the logic board for it to start

up and run the OS X, so if it seemed to have none, until you installed the 512MB chip in

the upgrade slot beneath the keyboard, there may be problems with the on-board RAM

that was installed permanently by the factory. If so, then other problems may result.

Also, a hard disk drive that's worn to the point of near failure can act up in strange ways, as

data corruption can affect the system functions and damage applications, as part of a variety

of symptoms. A hardware test, usually included on one of the original iBook system discs,

could be marginally helpful, to find some issues.

Safe Boot mode can be accessed on restart of the computer with the Shift key held down

which could allow you to see if the machine, or just the main user account, has an issue.

If you have a second user account, you could try that to see if a problem is based on one

set of installed applications and settings in the main account. A less cluttered one may be

free of the other account issues. You can also make a second account, in Admin level,

for testing purposes. -- See this support link for details regarding that process:

•Try safe mode if your Mac doesn't finish starting up -- Apple Support

Does the computer start in SafeBoot mode, where you could test and see if any specific set

of your actions, such as disk utility? Or perhaps a repair of the hard drive while booted from

the OS X 10.4 install DVD? The Disk Utility on installer DVD, accessed from menu options

prior to running any other installer function, can be used to attempt repair, reformat, reinstall

and other functions, including ready a new HDD for installation or prepare a second HDD to

be used as a location for a bootable system clone or copy. It is versatile. Hold the C key down

while the Install DVD is in the optical drive, and restart the computer and keep the C key held

until you hear the drive workaway about 20 minutes or perhaps less, and you can see it goes

through the setup section to choose to re-install. Get past the language selection, and then

look for the Installer to provide a main menu bar such as an OS X window... & review options.

•Mac OS X - Using Disk Utility to Repair a Disk:

https://kb.wisc.edu/helpdesk/page.php?id=3810

•Resolve startup issues and perform disk maintenance with Disk Utility and fsck - Apple Support

What kinds of 'reset' were you referring to, having done? Some use that word interchangeably

with other functions that are not equal or similar in expectation. A PMU-reset only helps in a few

ways, and a PRAM-reset has specific limitations also. And then, some may do a restore install

or clean-install, and a few may call that a reset.

•Resetting PowerBook and iBook Power Management Unit (PMU) -- Apple Support

For general older OS X Maintenance and troubleshooting ideas and information, sites such as

this one can be helpful. The newest OS X versions have a few things in common with the old

but there are differences, such as the need to have a system DVD or if older, a CD; for the

model in question or a retail full install system disc of correct vintage for that model series.

•OS X Maintenance and Troubleshooting - macattorney:

http://www.macattorney.com/ts.html

With a older and likely tired portable computer, there are several areas in hardware & software

that could contribute to odd symptoms and to failures. Hard drives wear out faster in a portable.

If you have a second Mac with FireWire ports, it may be possible to boot the iBook into Target

Disk Mode and use a FireWire cable between it and a healthy Mac to check, test, and repair

the older computers hard disk drive. {Not to be confused with later Mac's Target Display Mode.}

•How to use and troubleshoot FireWire target disk mode - Apple Support

If you have external FireWire enclosed self-powered (AC adapter) hard disk drive, you could

also set it up as a test tool where a bootable system could be installed on the external drive in

such an enclosure, that may help discover or troubleshoot the internal hard drive. A good HDD

in an external FireWire enclosure can be used in older Power PC based Macs as a start drive.

The chipset in the enclosure would have to be similar to the Oxford chipset; some later model

external enclosures with FireWire ports (400/800) have a different chipset, and may also be

useful with other models of hardware architecture; some have four different kinds of ports.

(Note the OWC or macsales web site for a variety of useful items for Mac.)

Well, I am not sure what else to say, the processes that may help determine what is at fault or

failing in the computer are generally covered. And some trial-and-error is required to attempt

to find or repair faults in a computer, which may be hardware or software. Or a bit of both.

In any event...

Good luck & happy computing! 🙂