Thanks Texrat.
I'll actually download Ubuntu Desktop iso. Downloading directly from a UK based server so it should be done in about an hour

So I did some surfing and came across what I need to do:

. Burn ISO as bootable DVD
. Bootup Ubuntu at CMOS
. Load Xterm
. Type 'cd /mnt/chosen harddrive'
. Type 'ls'
. Type "--set-rd-flags=no-lifeguard-reset"
. Insert N800 via USB make sure it can switch on
. Then "--clear-rd-flags=no-lifeguard-reset" to turn the flag off.

and if that previous line doesn't work to clear flag then try:
"./flasher-3.0 --disable-rd-mode" then check with "./flasher-3.0 --query-rd-mode"

Is this all correct or have I missed something out :S