how to install language packs?

i have read the other posts here that deal with the same problem, and i have also read the documentation for translating several times to be sure i haven't missed anything.

im havent really found a concrete answer for this one, do i have to translate all of the pages?
atm i have only done the front page and not the administrator page. and i have overwritten the .ini file in Joomla/language/nb-NO.com_joobb.ini, and nothing happened, and i tried overwriting the en-GB file, i just edited the file name for it matches, but it still has the Norwegian word in it. i have tried emptying the memory of the joomla server, but still nothing. do i have to translate the joocm? or is it enough with just doing the joobb? and do i have to translate both sides(front page and admin page)
it kind of looks like one word has been translated... and that is where it says "all times are" it says "alle tider er" on my forum...

thanks for all help
Kniferr

EDIT:
im editing this post since i dont want to bmp it up, but now i think i have understoop how to do it, was a little tricky at first, since i didnt read the template translation that much since i thought that was only to do with the look of the board... but i notices that there were language files there to, im sorry to have bothered you ill try this solution, if i dont get it to work you can count on me beeing back

thanks for all the views
Kniferr