menu lists help

hi, 1st off i would like to say to everyone here, had a mac for 4 years now after many years of problems with windows and now this is my 1st problem.

i re installed my imac software after it all went wrong, i done a new install and wiped the hard drive, mac all running except on some of the drop down menus i get n numbers eg n236 instead of words, ie arrange as, open using. anybody had this or know what it is
many thanks
andy