okay, i'm horrible at explaining things, but i will do my best anyway, for some reason when after the initial new game question stuff at Doc Mitchell's house you get the option to activate hardcoe or not, i ALLWAYS play with hardcoe so i allways use the yes option, but for some reason it doesnt activate hardcoe when i select yes, and i'm pretty sure it did when i first played the game. i'm NOT sure its mod related, but i'm NOT sure if it isnt mod related... but i havent seen anyone else writing about this, or i'm not searching the right places.... so anyone know anything?..

Try going to the gameplay options and it says hardcoe than yes or no and make sure it says yes. If that doesnt work on steam right click on fallout new vegas go to properties go to local files
and click verify integrity of game cache, if all this fails either buy a new copy of the game or talk to bethesda customer support

why should i buy a new copy of the game becourse of one option? i only wanted to know if it was a known problem or if it was just me, achievements doesnt seem to work 100% of the time either..