remap using xmodmap
 

The o key on my keyboard doesn't work So how could I swap the # key on my keyboard with o using xmodmap?

Welcome to the forums.
Yes, this can be changed easily. First find out the code of your # key using xev command, then use:
xmodmap -e 'keycode XXX=o'
Replace XXX with keycode you got from xev.

hi thanks fr yr replying mate

i have tried the method u have mentioned before but it doesnt seem to wrk

it changes the keycode on xev

keycode for # is 49
whn i use xmodmap to remap it o and then check xev key code list for code 49 it shows it as o
but when i press # later on it still prints # nt o

The command needs to be executed on every X login, place it as a start up item so it sticks.

this might make me sound "thick"

but do you think you could walk me through it?

cheers