You could try installing NetBSD on it.
and most desktop systems can boot to a usable state.
Shame OpenOffice is far too bload to run on such an old machine, have you tried Abi Word?
by the way, if it is running macOS 7.5, then does this mean that even though it has a b/w screen, it is thinking in colour?
I have this same Mac on my network, with 16mb of ram (the max it will take) and a 700mb HD.
You can download System 7.5.5 for free from Apple's web site in their section of obsoleted software; I used floppies. It helps to have another Mac in the process to format the discs as HFS and also uncompress them while maintaining resource forks and other classic irritations.
The essential peripheral for any compact Mac is a SCSI > Ethernet adapter from Asante. This adapter came in two forms: one self-powered from the SCSI port, and another that required an AC adapter, but also provided a chainable SCSI port on the back for attaching stuff like extra hard drives, a CD ROM, etc. without detaching the ethernet adapter.
Important note regarding the adapter in any form: autosensing 10/100 or 10/100/1000 hubs cannot identify the Asante adapter; the only workaround is to spend dollars on a switch where each port can be manually assigned or to just attach an old 10 BaseT hub.
System 6 is nice on this Mac, but lacks built in TCP/IP if I remember correctly, so it requires digging and configuring things such as MacTCP -- not real fun. I opted to take the performance hit and go for 7.5.5, which isn't a big deal since I have the maximum amount of ram.
...OS X 10.4 cannot speak Appleshare over Appletalk, only Appleshare over TCP;
System 7.5.5 must use Appleshare over Appletalk; netatalk can do this, and can be configured on any Linux/BSD box.
The SCSI ethernet adapter is slow; do not expect any blazingly fast speeds. Moving data feels slower than dial up sometimes. NetBSD (and maybe Debian 68k) should be installable over the serial port, as the guy who owned mine previous to me had done that.
However, I do not believe Linux or BSD support the Asante ethernet adapter, so your outside communication will be limited to the serial port. If that sounds enticing to you, go for it I guess.
On the other hand, this machine will run up to Mac OS 8.1, and I think 8.1 (or 8) introduced built-in web sharing.
I'm using MacHTTP (others are probably fine as well, but do not let you change the default port).
Game wise, you'll want to check out Shufflepuck Cafe. All in all, it's probably not worth your time, and the money you'd waste on it you could get a G3 PowerMac (at least beige) and run something more modern -- like OS X. I only tinkered with mine out of boredom one weekend.
ok, well i have a DI-604 router. now, please bear in mind i am someone who is not even sure of the difference between a hub, a switch and a router, so when it comes to complicated terms like autosensing, i am out of my depth. i *may* have the manual for the router but as i recall it is useless (totally dumbed down and 100% microcentric), but i maybe the www knows something about whether it is autosensing or not.