Debian 3 was able to boot from a CD-R ("boot cdrom" seemed to work
fine) but seemed to crash after it freed kernel memory (either that or
for some reason it stopped sending output to the serial port).

I would be quite happy to run NetBSD but my attempts all failed. The
second floppy disk image was larger than a floppy disk, the CDROM ISO
image wasnt valid and wouldnt write properly (not corrupt, just not
created properly it seems). Tape booting seemed the most promising but
it couldnt read the second part from tape even though I had followed
the instructions exactly. I didnt have much success with network
booting either - it just gave errors I think. Ive never network booted
a computer so it is entirely possible I was doing somthing wrong.

SunOS is also fine by me - The machine is unlikely to be particularly
useful to me besides as an example of an older sun system in a lunchbox
case. As a result functionality or speed doesnt bother me much, as long
as it will boot into an operating system. The only reason why I havent
tried installing an old version of SunOS yet is because I dont have the
installation media and I dont know where i could get it from (I assume
it isnt licensed as free software).

At the moment I suspect that both of my 13w3 monitors have failed so I
have no real way to connect an actual display to the machine - I can
only use a null modem cable. Ive tested my 13w3 monitors on both the
IPC and my SPARCstation 5. The 17" SUN one that came with the IPC
doesnt display anything. After about a minute it makes a clicking noise
and turns off. It wont turn on again after this until ive left it for
an hour or so. My 20" SGI monitor makes some good noises but doesnt
display anything and after a few seconds its orange LED comes on.
Connecting them to a PC makes no difference (I have an adapter cable).

My SPARCstation 5 is currently dead (power led comes on straight away
for about half a second, turns off, drives spin up, nothing else
happens. I cant connect a serial cable as I dont have appropriate
adapters & monitors dont seem to work so I have no idea whats wrong).
As a result of its deadness tape booting anything will be difficult -
it was my only linux box with SCSI.

So, any ideas on how I can install Linux or NetBSD from CDROM or
network? (following the netbsd installation instructions for either
didnt get me far)